软件测试 Web自动化测试 基础知识 HTML CSS JavaScript

文章目录

    • 1 HTML
      • 1.1 HTML简述
      • 1.1.2 常用基本标签
      • 1.1.3 表格
      • 1.1.4 表单(重点)
        • 表单小结
      • HTML小结
    • 2 CSS样式表
      • 2.1 三种格式修改样式
        • 2.1.1 行内样式(尽量不用)
        • 2.1.2 内部样式
        • 2.1.3 外部样式(最佳办法)
      • 2.2 常见的选择器
      • 2.3 常见的背景样式属性
      • CSS样式表小结
    • 3 JavaScript
      • 3.1 JavaScript基本概念
        • 3.1.1 什么是JavaScript?
        • 3.1.2 JavaScript特点
        • 3.1.3 js和java的区别
        • 3.1.4 JavaScript核心
      • 3.2 JavaScript基础语法
        • 3.2.1 如何在网页中写JavaScript(重点)
        • 3.2.2 JavaScript语法(重点)
        • 3.2.3 JavaScript的数据类型
        • 3.2.4 变量的定义与使用
        • 3.2.5 赋值运算符
      • 3.3 JavaScript流程控制
        • 3.3.1 if语句
        • 3.3.2 switch语句
        • 3.3.3 for语句
        • 3.3.4 while语句
        • 3.3.5 do-while语句
      • 3.4 函数
        • 3.4.1 函数的定义
        • 3.4.2 函数的调用
        • 3.4.3 匿名函数
        • 3.4.4 全局函数
      • 3.5 事件
        • 3.5.1 常见的事件
        • 3.5.2 事件处理
      • 3.6 正则表达式
      • 3.7 Cookies
        • 3.7.1 创建cookie
        • 3.7.2 读取 cookie
        • 3.7.3 改变 cookie
        • 3.7.4 删除 cookie
        • 3.7.5 cookie 字符串
        • 3.7.6 JavaScript Cookie 实例
        • JavaScript小结
    • 总结

1 HTML

1.1 HTML简述

HTML概念
HTML (Hyper Text Markup Language超文本标识语言),是一种用来制作超文本文档的简单标记语言。
用HTML编写的超文本文件称为HTML文件,也称Web文件。
HTML是Web开发的基本技术。

HTML文件的基本结构

<html>
	<head>
		<title>title>
	head>
	<body>
	body>
html>

……< /html> 标签标记HTML文档的开始和结束。
< /head> 头部部分。
</ title></code> 网页标题。<br> <code><body>< /body</code>> 网页内容,可以是文本。图像等。</p> <p>例如:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> 这是我的第一个页面! <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/6df2598a8d2947aa947cd973a7e163bc.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/6df2598a8d2947aa947cd973a7e163bc.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第1张图片" width="650" height="204" style="border:1px solid black;"></a></p> <p>HTML标签<br> HTML 标记标签通常被称为HTML标签(HTML tag)。<br> HTML标签是由尖括号包围的关键词。比如<code><html></code>。<br> HTML标签通常是成对出现的,比如<code><b></code>和<code></b></code>。<br> 标签对中的第一个标签是开始标签,第二个标签是结束标签。<br> 开始和结束标签也被称为开放标签和闭合标签。</p> <p>HTML元素<br> HTML元素指的是从开始标签到结束标签的所有代码,是HTML语言的基本部分。HTML文档由嵌套的HTML元素构成。html标签里面有head元素、title元素和boby元素。<br> 空的HTML元素。<strong>没有内容的HTML元素被称为空元素</strong>。空元素是在开始标签中关闭的。<code><br></code>(定义换行的标签)就是没有关闭标签的空元素。</p> <p>HTML元素属性<br> HTML元素可以有自己的相关属性,属性为HTML元素提供附加信息。<strong>属性</strong>通常添加在元素的开始标签当中,属性值带双引号。<br> 例:</p> <pre><code class="prism language-html"> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h1</span> <span class="token attr-name">align</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>center<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>This is heading 1<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h1</span><span class="token punctuation">></span></span> </code></pre> <p>页面背景色或背景图像</p> <pre><code class="prism language-html"> <span class="token comment"><!---设置背景颜色--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span> <span class="token attr-name">bgcolor</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>red<span class="token punctuation">"</span></span> <span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token comment"><!---设置背景照片--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span> <span class="token attr-name">background</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/2.png<span class="token punctuation">"</span></span> <span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> </code></pre> <h3>1.1.2 常用基本标签</h3> <p>常用基本标签分为有块元素和行内元素。</p> <p>块元素<br> 块元素,在页面中独占一行的元素称为块元素(block element)。<br> <strong>块元素包括标题、段落、换行、链接、图像、注释和嵌入元素(音频、视频)。</strong><br> <strong>1 标题</strong><br> 在网页中HTML专门用来负责网页的结构,所以在使用html标签中,应该关注的是标签的语义,而不是它的样式。<br> 标题标签:<br> h1~h6 一共六级标题;<br> h1最重要,h6最不重要;<br> h1在网页中的重要性仅次于title标签;<br> 一般情况下标题标签只会使用h1~ h 3,h 4~h 6很少使用。<br> 标题标签都是块元素,在页面中独占一行的元素称为块元素(block element)。</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h1</span><span class="token punctuation">></span></span>一级标题<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h1</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h2</span><span class="token punctuation">></span></span>二级标题<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h2</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h3</span><span class="token punctuation">></span></span>三级标题<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h3</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h4</span><span class="token punctuation">></span></span>四级标题<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h4</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h5</span><span class="token punctuation">></span></span>五级标题<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h5</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>h6</span><span class="token punctuation">></span></span>六级标题<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>h6</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/4f92d1724c42485b831eb9064c181c51.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/4f92d1724c42485b831eb9064c181c51.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第2张图片" width="650" height="637" style="border:1px solid black;"></a></p> <p><strong>2 段落</strong><br> 在p标签中的内容就表示一个段落。属于块元素。</p> <pre><code class="prism language-html"> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span><span class="token punctuation">></span></span>在p标签中的内容就表示一个段落<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span><span class="token punctuation">></span></span>在p标签中的内容就表示一个段落<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/7415a9216a3a4488b1fec15a444b20f9.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/7415a9216a3a4488b1fec15a444b20f9.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第3张图片" width="650" height="387" style="border:1px solid black;"></a><br> p标签和平标签之间有换行的效果。<br> p标签还有align属性。该属性有right、left和center属性值。<br> <a href="http://img.e-com-net.com/image/info8/6ed05fdb3aa848bdb13f4f6b048874e4.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/6ed05fdb3aa848bdb13f4f6b048874e4.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第4张图片" width="650" height="299" style="border:1px solid black;"></a></p> <p><strong>3 换行</strong><br> br换行。</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> 今天天气很好<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 今天心情很好 <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/5b017f1941c74d98b1ca56878ae88275.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/5b017f1941c74d98b1ca56878ae88275.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第5张图片" width="650" height="289" style="border:1px solid black;"></a></p> <p><strong>4 链接</strong><br> 超链接可以让我们从一个页面跳转到其他页面,或者是当前页面的其他位置。<br> <strong>href属性</strong><br> href指定跳转的目标路径,值可以是一个外部网站的地址,也可以是一个内部页面的地址。<br> 超链接是一个行内元素,在a标签中可以嵌套除它自身外的任何元素。<br> href属性值为#,回到当前页面的顶部。 这样点击超链接以后页面不会发生跳转,还是在当前的页面。</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>http://www.baidu.com<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>点击跳转百度<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>sucess.html<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>点击跳转内部页面<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>a</span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>#<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>回到顶部<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>a</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/459542741c7441dc9abecbc60982f33f.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/459542741c7441dc9abecbc60982f33f.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第6张图片" width="650" height="296" style="border:1px solid black;"></a></p> <p><strong>target属性</strong><br> 用于指定超链接打开的位置<br> 属性值:_self 默认值 在当前页面中打开超链接,即刷掉当前页面,转跳到指定链接;_blank 在一个新的页面中打开超链接。<br> _blank属性值例子如下:<br> <a href="http://img.e-com-net.com/image/info8/17b3343bf2f24a90b8d22eba4370c662.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/17b3343bf2f24a90b8d22eba4370c662.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第7张图片" width="650" height="294" style="border:1px solid black;"></a><br> <a href="http://img.e-com-net.com/image/info8/996af11fd8f440baae69c226a59c5567.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/996af11fd8f440baae69c226a59c5567.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第8张图片" width="650" height="260" style="border:1px solid black;"></a></p> <p><strong>5 图像</strong><br> 使用img标签来引入外部图片,img标签是一个自结束标签。<br> img这种元素属于替换元素(块元素和行内元素之间,具有两种元素的特点)<br> 属性:<br> src属性指定的是外部图片的路径。<strong>该图片可以是项目里的照片,也可以是网上的照片。</strong><br> alt属性图片的描述,这个描述默认情况下不会显示,有些浏览器在图片无法加载是显示,搜索引擎会根据alt中的内容来识别图片。<br> width图片的宽度(单位是像素)。<br> height图片的高度,宽度和高度如果值修改了一个,则另一个会等比例缩放。</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>img</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/1-1.jpg<span class="token punctuation">"</span></span> <span class="token attr-name">alt</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>分词<span class="token punctuation">"</span></span> <span class="token attr-name">width</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>500<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>img</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>https://img1.baidu.com/it/u=4264004400,2710433939&fm=26&fmt=auto&gp=0.jpg<span class="token punctuation">"</span></span> <span class="token attr-name">alt</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>保时捷<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/18ea35e35c4344d4877282038798d00d.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/18ea35e35c4344d4877282038798d00d.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第9张图片" width="650" height="306" style="border:1px solid black;"></a></p> <p>注意:<br> 一般情况在pc端,不建议修改图片的大小,需要多大的图片就裁多大,但在移动端经常需要对图片进行缩放(大图缩小)</p> <p>图片格式<br> jpeg(jpg)<br> 支持的颜色比较丰富,不支持透明效果,不支持动图;一般用来显示照片。<br> gif<br> 支持的颜色比较少,支持简单透明,支持动图;颜色单一的图片,动图。<br> png<br> 支持的颜色丰富,支持复杂透明,不支持动图;专为网页而生<br> webp<br> 这种格式是谷歌新推出的专门用来表示网页中的图片的一种格式,它具备其他图片格式的所有优点,而且文件还特别小;缺点:兼容性不好。<br> <strong>原则:效果一样,用小的,效果不一样,用效果好的!</strong><br> base64(类似加密技术)<br> 将图片使用base64编码,这样可以将图片转换为字符,通过字符的形式来引入图片;一般都是一些需要和网页一起加载的图片才会使用base64。<br> 问:如何将图片转换为base64?<br> 第一,上百度搜索 base64在线图片;第二,把照片转换为base64码;第三,将base64码复制到src属性的属性值里面。</p> <p><strong>6 注释</strong><br> 作用:注释中的内容会被浏览器忽略,不会在网页中直接显示,但是可以在源码中查看注释,注释用来对代码进行解释说明的;开发中一定要养成良好的编写注释的习惯,注释要求简单明了;注释还可以将一些不希望显示的内容隐藏。<br> 注:<br> 注释不能嵌套!!<br> <strong>7 嵌入元素(音频、视频)</strong><br> <strong>音频</strong>可以使用audio标签,source标签和embed标签。<br> audio 标签用来向页面中引入一个外部的音频文件,音视频文件引入时,默认情况下不允许用户自己控制播放停止。<br> audio 标签的属性:<br> controls 是否允许用户控制播放<br> autoplay 音频文件是否自动播放,如果设置了autoplay ,则音乐在打开页面时会自动播放,但是目前大部分浏览器都不会自动对音乐进行播放。<br> loop 音乐是否循环播放。</p> <p>例子:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>audio</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/邓园长 说好的幸福呢.mp3<span class="token punctuation">"</span></span> <span class="token attr-name">controls</span> <span class="token attr-name">loop</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>audio</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>效果如下:<br> <a href="http://img.e-com-net.com/image/info8/4ee81bacacf14dd4afbfa40fc0002139.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/4ee81bacacf14dd4afbfa40fc0002139.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第10张图片" width="508" height="145" style="border:1px solid black;"></a><br> 使用source标签</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>audio</span> <span class="token attr-name">controls</span> <span class="token attr-name">autoplay</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>source</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/邓园长 说好的幸福呢.mp3<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>source</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/邓园长 说好的幸福呢.agg<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>audio</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>mp3格式适应大多数浏览器。<br> agg格式音频适应ios系统浏览器。<br> 此外,还有embed 标签用来适应旧的浏览器(ie 8),ie 8无法识别audio标签。<br> 综上,得出适应所有浏览器的音频播放,如下:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>audio</span> <span class="token attr-name">controls</span> <span class="token attr-name">autoplay</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>source</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/邓园长 说好的幸福呢.mp3<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>source</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/邓园长 说好的幸福呢.agg<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>embed</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/邓园长 说好的幸福呢.mp3<span class="token punctuation">"</span></span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>audio/mp3<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>audio</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p><strong>视频</strong><br> 使用video标签来向网页中引入一个视频,使用方法和audio基本是一样的。<br> 引用本地的视频,将视频放到项目中</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>video</span> <span class="token attr-name">controls</span> <span class="token attr-name">autoplay</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>source</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./picture/杨千嬅 可惜我是水瓶座 .mp4<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>video</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>引用外部视频,找到视频的嵌入代码,</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <iframe src="//player.bilibili.com/player.html?aid=803421388&bvid=BV1ey4y137C6&cid=350369745&page=1" scrolling="no" border="0" frameborder="no" framespacing="0" allowfullscreen="true > <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>iframe</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/47c830b75dff4a3d900e5f509bd85d55.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/47c830b75dff4a3d900e5f509bd85d55.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第11张图片" width="650" height="326" style="border:1px solid black;"></a></p> <p>行内元素<br> 加粗<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>b</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>b</span><span class="token punctuation">></span></span> </code></pre> <p>大号<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>big</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>big</span><span class="token punctuation">></span></span> </code></pre> <p>小号<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>small</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>small</span><span class="token punctuation">></span></span> </code></pre> <p>着重文字<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>em</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>em</span><span class="token punctuation">></span></span> </code></pre> <p>斜体标签<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>i</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>i</span><span class="token punctuation">></span></span> </code></pre> <p>删除标签<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>del</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>del</span><span class="token punctuation">></span></span> </code></pre> <p>下划线标签<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>ins</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>ins</span><span class="token punctuation">></span></span> </code></pre> <p>上标<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>sup</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>sup</span><span class="token punctuation">></span></span> </code></pre> <p>下标<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>sub</span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>sub</span><span class="token punctuation">></span></span> </code></pre> <p>修饰标签<br> 格式如下:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>font</span> <span class="token attr-name">color</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span><span class="token punctuation">"</span></span> <span class="token attr-name">size</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span><span class="token punctuation">"</span></span><span class="token punctuation">></span></span>xxxx<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>font</span><span class="token punctuation">></span></span> </code></pre> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> 今天天气<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>b</span><span class="token punctuation">></span></span>很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>b</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 今天天气<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>small</span><span class="token punctuation">></span></span>很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>small</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 今天天气<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>em</span><span class="token punctuation">></span></span>很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>em</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 今天天气<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>i</span><span class="token punctuation">></span></span>很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>i</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 3 <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>sup</span><span class="token punctuation">></span></span>2<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>sup</span><span class="token punctuation">></span></span>=9<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> H<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>sub</span><span class="token punctuation">></span></span>2<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>sub</span><span class="token punctuation">></span></span>O<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>font</span> <span class="token attr-name">color</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>red<span class="token punctuation">"</span></span> <span class="token attr-name">size</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>10px<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>今天天气很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>font</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>效果如下:<br> <a href="http://img.e-com-net.com/image/info8/ba755cb047ec46daa984cdd17545ca72.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/ba755cb047ec46daa984cdd17545ca72.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第12张图片" width="523" height="523" style="border:1px solid black;"></a></p> <h3>1.1.3 表格</h3> <p>表格由<code><table></code>标签来定义。<br> 每个表格均有若干行(由<code><tr></code>标签定义),每行被分割为若干单元格(由<code><td></code>标签定义)。<br> 字母td指表格数据(table data),即数据单元格的内容。数据单元格可以包含文本、图片、列表、段落、表单、水平线、表格等等。<br> 三个元素必须一起使用,否则无法定义表格。</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>table</span> <span class="token attr-name">border</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>3<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>section</span><span class="token punctuation">></span></span>乘法表<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>section</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>th</span><span class="token punctuation">></span></span>1<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>th</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>th</span><span class="token punctuation">></span></span>2<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>th</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>th</span><span class="token punctuation">></span></span>3<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>th</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>tr</span><span class="token punctuation">></span></span><span class="token comment"><!-- 第一行 --></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span>1*1=1<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>tr</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>tr</span><span class="token punctuation">></span></span><span class="token comment"><!-- 第二行 --></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span>1*2=2<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span>2*2=4<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>tr</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>tr</span><span class="token punctuation">></span></span><span class="token comment"><!-- 第三行 --></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span>1*3=3<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span>2*3=6<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>td</span><span class="token punctuation">></span></span>3*3=9<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>td</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>tr</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>table</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/e75053514dd042eebb086a38d5f69fb4.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/e75053514dd042eebb086a38d5f69fb4.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第13张图片" width="359" height="250" style="border:1px solid black;"></a><br> section为表格的标题,th可以看做td的加粗形式,tr为行标识,td为表格内容。在td标签中还有bgcolor属性和align属性。</p> <h3>1.1.4 表单(重点)</h3> <p>HTML表单用于搜集不同类型的用户输入。最常见最典型的表单即注册页面。<br> 表单是一个包含表单元素的区域。<br> 表单元素是允许用户在表单中(比如:文本域、下拉列表、单选框、复选框等等)输入信息的元素。<br> 表单使用表单标签(<code><form></code>)定义。<br> 基本格式如下 :</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>FORM</span> <span class="token attr-name">Action</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>url<span class="token punctuation">"</span></span> <span class="token attr-name">Method</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>*<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>input</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>FORM</span><span class="token punctuation">></span></span> </code></pre> <p>表单的三个要点<br> 表单控件(Form Controls)<br> 动作属性(Action)<br> 方法属性(Method)</p> <p>表单控件(Form Controls)<br> 通过HTML表单的各种控件,用户可以输入文字信息,或者从选项中选择,以及做提交的操作。<br> from标签中有input标签、select标签和textarea标签。</p> <p>form标签中有action属性和method属性。<br> action属性<br> 当用户单击确认按钮(即提交表单)时,表单的内容会被传送到另一个文件。表单的动作属性定义了目的文件的文件名。由动作属性指向的这个文件通常会对接收到的输入数据进行相关的处理。<br> method属性<br> method属性告诉浏览器如何将编码后的数据发给服务器。其值为get或者post。<br> get属性值,浏览器会将数据直接附在表单的 action url之后。这两者之间用问号进行分隔<br> post属性值,直接连接服务器,然后将html表单中的值发送给web服务器。这种方式是没有字符长度限制的。</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>form</span> <span class="token attr-name">action</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span><span class="token punctuation">"</span></span> <span class="token attr-name">method</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>get<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>form</span><span class="token punctuation">></span></span> </code></pre> <p>action属性作用是提交表单之后跳转的页面,可以是项目内部的页面,也可以是外部链接;method属性为提交方式,get属性值在提交之后表单的属性值会显示在地址栏,地址后先接?,然后接各个控件的值,如下图:<br> <a href="http://img.e-com-net.com/image/info8/b4c7d4425640407a97efb2903a6232fc.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/b4c7d4425640407a97efb2903a6232fc.jpg" alt="在这里插入图片描述" width="650" height="48"></a></p> <p>而post属性值则不会。</p> <p>input标签有name属性和value属性,根据tpye属性还可以有checked属性,checked作用是默认选项。<br> input标签中type属性可分为几个属性值:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">tpye</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token comment"><!--文本框--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">tpye</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>password<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token comment"><!--密码框--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">tpye</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>radio<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token comment"><!--单选框--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">tpye</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>checkbox<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token comment"><!--复选框--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">tpye</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>button<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token comment"><!--普通按钮--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">tpye</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>reset<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token comment"><!--重置按钮--></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">tpye</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>submit<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token comment"><!--提交按钮--></span> </code></pre> <p>例子如下:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>form</span> <span class="token attr-name">action</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span><span class="token punctuation">"</span></span> <span class="token attr-name">method</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>get<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> 用户名<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>userame<span class="token punctuation">"</span></span> <span class="token attr-name">maxlength</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>20<span class="token punctuation">"</span></span> <span class="token attr-name">size</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>10px<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 密 码<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>password<span class="token punctuation">"</span></span> <span class="token attr-name">maxlength</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>20<span class="token punctuation">"</span></span> <span class="token attr-name">size</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>10px<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 性别 <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>radio<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>sex<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>man<span class="token punctuation">"</span></span> <span class="token attr-name">checked</span><span class="token punctuation">></span></span>男 <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>radio<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>sex<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>woman<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>女<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 选择你喜欢的动漫是:<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>checkbox<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cb01<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>1<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>海贼王 <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>checkbox<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cb02<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>2<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>火影 <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>checkbox<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cb03<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>3<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>死神 <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>checkbox<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cb04<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>4<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>刃牙<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 选择你喜欢的食物: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>select</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>sel<span class="token punctuation">"</span></span> <span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>option</span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>miketea<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>奶茶<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>option</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>option</span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>chocolate<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>巧克力<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>option</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>option</span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cake<span class="token punctuation">"</span></span> <span class="token attr-name">selected</span><span class="token punctuation">></span></span>蛋糕<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>option</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>select</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 大声说出你的想法: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>textarea</span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text<span class="token punctuation">"</span></span> <span class="token attr-name">id</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>teext1<span class="token punctuation">"</span></span> <span class="token attr-name">cols</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>30<span class="token punctuation">"</span></span> <span class="token attr-name">rows</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>20<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>textarea</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>button<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>but<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>普通按钮<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>reset<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>resetbutton<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>重置按钮<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>submit<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>sub<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>提交按钮<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>form</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/5458bf5b14324f368c3e6d71546d904c.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/5458bf5b14324f368c3e6d71546d904c.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第14张图片" width="457" height="806" style="border:1px solid black;"></a></p> <p>分析:<br> input标签中的type属性的属性值为text时,maxlength属性为文本框最多输入的数字的容量。<br> 在input标签中添加checked属性,将该选项设置为默认选项。<br> 想要实现单选的效果,第一,type属性的属性值为radio;第二,<strong>各个选项的name属性的属性值必须保持一致</strong>。<br> 相反,想要实现复选的效果,第一,tyoe属性的属性为checkbox,各个选项的name属性的属性值必须不一致。<br> select标签表示下拉框,在select标签中的option标签中添加selected属性,表示默认选项,若选择中没有添加selected属性,则第一个为默认选项。<br> textarea标签表示文本域,其中的cols属性控制列,rows控制行。</p> <h4>表单小结</h4> <p><a href="http://img.e-com-net.com/image/info8/878b1e4cb8794604a31bb83a458a34d6.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/878b1e4cb8794604a31bb83a458a34d6.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第15张图片" width="650" height="183" style="border:1px solid black;"></a><br> 拓展<br> HTML5表单新的input标签的属性值<br> color 用于选取颜色<br> date选择一个日期<br> datetime-local选择一个日期和时间(无时区)<br> email包含e-mail地址的输入域<br> month选择一个月份<br> number包含数值的输入域<br> time选择一个时间<br> url包含URL地址的输入域,在提交表单时,会自动验证url域的值<br> week选择周</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>type新属性值<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>form</span> <span class="token attr-name">action</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>success.html<span class="token punctuation">"</span></span> <span class="token attr-name">method</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>get<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> 选取颜色:<span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>color<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 日期: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>date<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 日期: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>datetime-local<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 时间: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>time<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 周: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>week<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 月: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>month<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 输入数字: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>number<span class="token punctuation">"</span></span> <span class="token attr-name">max</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>20<span class="token punctuation">"</span></span> <span class="token attr-name">min</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>0<span class="token punctuation">"</span></span> <span class="token attr-name">step</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>2<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>2<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 邮件: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>email<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> 地址: <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>url<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>br</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>input</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>submit<span class="token punctuation">"</span></span> <span class="token attr-name">name</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>sub<span class="token punctuation">"</span></span> <span class="token attr-name">value</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>提交<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>form</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行并填入数据,效果如下图:<br> <a href="http://img.e-com-net.com/image/info8/4480ceb0819c4c83a387aaf88a3dcf25.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/4480ceb0819c4c83a387aaf88a3dcf25.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第16张图片" width="549" height="709" style="border:1px solid black;"></a><br> number属性值还有其他的属性。max规定的最大值,min规定的最小值,step规定的步长,value规定默认值。</p> <h3>HTML小结</h3> <p>HTML常用基本标签分为有块元素和行内元素。<br> 表单使用表单标签(<code><form></code>)定义。form标签有两个重要属性action属性和method属性,action属性作用是当用户单击确认按钮(即提交表单)时,表单的内容会被传送到另一个文件。method属性告诉浏览器如何将编码后的数据发给服务器。其值为get或者post。表单中用input标签设置文本框、密码框、单选框和复选框,用select标签设置下拉框,用textarea标签设置文本域。<br> HTML5表单新的input标签的属性值。是关于颜色、日期、时间、邮箱和url的属性值。</p> <h2>2 CSS样式表</h2> <p>CSS就是层叠样式表,网页实际上是一个多层的结构,通过CSS可以分别为网页的每一个层来设置样式,而最终我们能看到只是网页的最上边一层。总之,CSS用来设置网页中元素的样式。</p> <p>CSS样式表的基本结构</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>style</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text/css<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token style"><span class="token language-css"> <span class="token selector">选择器</span> <span class="token punctuation">{</span> <span class="token property">属性1</span><span class="token punctuation">:</span>属性值<span class="token punctuation">;</span> <span class="token property">属性2</span><span class="token punctuation">:</span>属性值<span class="token punctuation">;</span> <span class="token property">属性3</span><span class="token punctuation">:</span>属性值<span class="token punctuation">;</span> …… <span class="token punctuation">}</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>style</span><span class="token punctuation">></span></span> </code></pre> <h3>2.1 三种格式修改样式</h3> <p>CSS有3种格式修改元素的样式:行内修改样式、内部样式表和外部样式表。</p> <h4>2.1.1 行内样式(尽量不用)</h4> <p>如下例子:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span> <span class="token special-attr"><span class="token attr-name">style</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span><span class="token value css language-css"><span class="token property">color</span><span class="token punctuation">:</span>red<span class="token punctuation">;</span><span class="token property">font-size</span><span class="token punctuation">:</span>20px<span class="token punctuation">;</span></span><span class="token punctuation">"</span></span></span><span class="token punctuation">></span></span>今天天气很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>在标签内部通过style属性来设置元素的样式。<br> 缺点:使用内联样式,样式只能对一个标签生效。如果希望影响多个元素必须在每一个元素都要复制一遍,并且当样式发生变化时,我们必须要一个一个的修改,非常不方便,所以在开发时绝对不要使用内联样式!</p> <h4>2.1.2 内部样式</h4> <p>将样式编写到head中的style标签里,然后通过CSS选择器来选中元素并为其设置各种样式,可以同时为多个标签设置样式,并且修改时只需要修改一处即可。内部样式表更加方便对样式进行复用。<br> 缺点:<strong>内部样式表只能对一个网页起作用</strong>,它里边的样式不能跨页面进行复用。<br> 如下例子:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>style</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text/css<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token style"><span class="token language-css"> <span class="token selector">p</span><span class="token punctuation">{</span> <span class="token property">color</span><span class="token punctuation">:</span> red<span class="token punctuation">;</span> <span class="token property">font-size</span><span class="token punctuation">:</span> 20px<span class="token punctuation">;</span> <span class="token punctuation">}</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>style</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span><span class="token punctuation">></span></span>今天天气很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <h4>2.1.3 外部样式(最佳办法)</h4> <p>可以将CSS样式编写到一个外部的CSS文件中,然后通过link标签来引入外部的文件。<br> 外部样式表需要通过link标签进行引入,意味着只要想使用这些样式都可以对其进行引用,样式就可以在不同的网页之间进行复用。<br> 将样式编写到外部的CSS文件中,可以使用到浏览器的缓冲机制,从而加快网页的加载速度。<br> 首先,新建css文件,如下图:<br> <a href="http://img.e-com-net.com/image/info8/ba80dff1f994472a8366f56445e102f4.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/ba80dff1f994472a8366f56445e102f4.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第17张图片" width="221" height="403" style="border:1px solid black;"></a><br> 然后,在网页中用link标签将网页和CSS文件关联起来,</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token comment"><!-- <style type="text/css"> p{ color: red; font-size: 20px; } </style> --></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>link</span> <span class="token attr-name">rel</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>stylesheet<span class="token punctuation">"</span></span> <span class="token attr-name">href</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>./css/CSS外部样式表.css<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span><span class="token punctuation">></span></span>今天天气很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/59edf429b5c34e328c27ad63af751f2d.png" target="_blank"><img src="http://img.e-com-net.com/image/info8/59edf429b5c34e328c27ad63af751f2d.png" alt="在这里插入图片描述" width="239" height="82"></a><br> 此外,还可以使用import关键字导入CSS样式表,比较少用,例子如下:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>style</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text/css<span class="token punctuation">"</span></span><span class="token attr-name">;</span><span class="token punctuation">></span></span><span class="token style"><span class="token language-css"> <span class="token atrule"><span class="token rule">@import</span> <span class="token string">"css/CSS外部样式表.css"</span><span class="token punctuation">;</span></span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>style</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>p</span><span class="token punctuation">></span></span>今天天气很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>p</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>结论:在html文件写结构,在CSS文件写样式,在html用link标签将CSS样式表引入。或者通过import导入CSS样式表。</p> <h3>2.2 常见的选择器</h3> <p>常见的选择器有元素选择器,class选择器,id选择器,类选择器,通配选择器,伪类选择器。</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>style</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text/css<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token style"><span class="token language-css"> <span class="token selector">ins</span><span class="token punctuation">{</span> <span class="token property">color</span><span class="token punctuation">:</span> red<span class="token punctuation">;</span> <span class="token property">font-size</span><span class="token punctuation">:</span> 20px<span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token selector">.underline</span><span class="token punctuation">{</span> <span class="token property">color</span><span class="token punctuation">:</span> blue<span class="token punctuation">;</span> <span class="token punctuation">}</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>style</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>ins</span> <span class="token attr-name">class</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>underline<span class="token punctuation">"</span></span><span class="token punctuation">></span></span>今天心情很好<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>ins</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/0f9d6ae8c8e84e42ba0f4ebfc93421b5.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/0f9d6ae8c8e84e42ba0f4ebfc93421b5.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第18张图片" width="650" height="172" style="border:1px solid black;"></a></p> <p>结论:class选择器的优先级大于标签选择器的优先级。class选择器样式用“.”来引用。</p> <h3>2.3 常见的背景样式属性</h3> <p>backgroud-color属性。设置背景颜色。<br> backgroud-image属性。设置背景图像。url值填入照片的路径。<br> backgroud-repeat属性。repeat-x属性值图片向左右重叠,repeat-y属性值图片向上下重叠,no-repeat属性值图片不重叠,保持照片原始大小。repeat属性值照片重复重叠。</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>style</span> <span class="token attr-name">type</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>text/css<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token style"><span class="token language-css"> <span class="token selector">body</span><span class="token punctuation">{</span> <span class="token property">background-image</span><span class="token punctuation">:</span> <span class="token url"><span class="token function">url</span><span class="token punctuation">(</span>picture/1.png<span class="token punctuation">)</span></span><span class="token punctuation">;</span> <span class="token property">background-repeat</span><span class="token punctuation">:</span> repeat-x<span class="token punctuation">;</span> <span class="token punctuation">}</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>style</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行效果如下:<br> <a href="http://img.e-com-net.com/image/info8/55f741462c364631ba89fc88f5f685e2.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/55f741462c364631ba89fc88f5f685e2.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第19张图片" width="650" height="174" style="border:1px solid black;"></a></p> <h3>CSS样式表小结</h3> <p>CSS样式表有三种修改样式方法:行内样式、内部样式和外部样式。<br> 常见的选择器有:元素选择器,class选择器,id选择器,类选择器,通配选择器,伪类选择器。<br> 常见的背景样式属性有:backgroud-color属性、backgroud-image属性和backgroud-repeat属性。</p> <h2>3 JavaScript</h2> <p>基本语法是:在网页中写JavaScript代码、JavaScript的语法与关键字、JavaScript的数据类型、变量的定义与使用和运算符的应用。</p> <h3>3.1 JavaScript基本概念</h3> <p>JavaScript 是属于HTML 和Web的编程语言。</p> <h4>3.1.1 什么是JavaScript?</h4> <p>JavaScript诞生于1995年。它当时的目的是为了<strong>验证表单输入的验证</strong>。因为在JavaScript问世之前,表单的验证都是通过服务器端验证的。而当时都是电话拨号上网的年代,服务器验证数据是一件非常痛苦的事情。经过许多年的发展,JavaScript 从一个简单的输入验证成为一门强大的编程语言。</p> <p>JavaScript是一种具有面向对象能力的、解释型的程序设计语言。<br> 更具体一点,它是<strong>基于对象</strong>和<strong>事件驱动</strong>并具有相对安全性的<strong>客户端脚本语言</strong>。因为他不需要在一个语言环境下运行,而只需要支持它的浏览器即可。它的主要目的是,验证发往服务器端的数据、增加Web互动、加强用户体验度等。<br> 基于对象:提供好了很多对象,可以直接拿过来使用。<br> 事件驱动:html做网站静态效果,javaScript实现动态效果。<br> 客户端:专门指的是浏览器。<br> JS的作用:操作HTML和CSS。</p> <h4>3.1.2 JavaScript特点</h4> <p>松散型:JavaScript语言核心与C、C++、Java相似,比如条件判断、循环、运算符等。但,它却是一种松散类型的语言,也就是说,它的变量不必具有一个明确的类型。<br> 解释型:不需要编译。浏览器直接解释执行。<br> 基于对象:我们可以直接使用JS已经创建的对象。Math String<br> 安全性:不允许访问本地硬盘,不能将数据写入到服务器上。<br> 跨平台:js依赖于浏览器本身,与操作系统无关。</p> <h4>3.1.3 js和java的区别</h4> <p>JavaScript和Java没有任何关系,属于两门编程语言。<br> 开发公司<br> Java是sun公司开发的,现在是oracle公司。<br> JS是Netscape(网景公司)公司开发的<br> 对象<br> Java是面向对象的 new<br> JS是基于对象的<br> 数据类型<br> Java是强类型语言(每种变量都有确定的数据类型)例如:int i = “10”<br> JS是弱类型语言【变量的类型由值决定】例如:vari = 10,varj = “10”<br> 执行过程<br> Java需要现编译成字节码文件,然后再执行<br> JS只需解析就可以执行</p> <h4>3.1.4 JavaScript核心</h4> <p>一个完整的JavaScript应该由下列三个不同的部分组成。<br> 1 核心(ECMAScript)<br> ECMA:欧洲计算机协会,由ECMA组织制定的js语法,语句,函数等<br> 2 文档对象模型(DOM)<br> Document Object Model:文档对象模型<br> 3 浏览器对象模型(BOM)<br> Broswer Object Model:浏览器对象模型</p> <h3>3.2 JavaScript基础语法</h3> <p>JavaScript 语法是一套规则,它定义了 JavaScript 的语言结构。</p> <h4>3.2.1 如何在网页中写JavaScript(重点)</h4> <p>方法1 在html页面中直接嵌入JavaScript</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span><span class="token punctuation">></span></span><span class="token script"><span class="token language-javascript"> js程序 </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> </code></pre> <p>js代码可以插入在<code><head></head></code>标签中间,也可以放在<code><body></body></code><br> 标签中间。<br> 最常用的是放在<code><head></head></code>。</p> <p>例子:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span><span class="token punctuation">></span></span><span class="token script"><span class="token language-javascript"> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"hello,world01~"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span><span class="token punctuation">></span></span><span class="token script"><span class="token language-javascript"> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"hello,world02~"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/d0d2953103c441ec83d961dd992f9e5e.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/d0d2953103c441ec83d961dd992f9e5e.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第20张图片" width="650" height="284" style="border:1px solid black;"></a><br> 点击确定,<br> <a href="http://img.e-com-net.com/image/info8/f8f679cf497549e784e2334041a98d8a.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/f8f679cf497549e784e2334041a98d8a.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第21张图片" width="650" height="282" style="border:1px solid black;"></a></p> <p>结论:如果同时在head标签和body标签写JS,则会先运行head标签里面的JS,然后再运行body标签里面的JS。</p> <p>方法2 引用外部的JavaScript(最常用的方法)</p> <p>首先,新建.js文件,在.js文件中,不需要<code><script></script></code>标签对括起来,例子如下:<br> <a href="http://img.e-com-net.com/image/info8/994138743f344c57a78309534770cd79.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/994138743f344c57a78309534770cd79.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第22张图片" width="650" height="345" style="border:1px solid black;"></a></p> <p>然后在html文件中链接js文件,使用如下语法:</p> <pre><code class="prism language-html"><span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>.js文件路径<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token script"></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> </code></pre> <p>具体例子如下:<br> <a href="http://img.e-com-net.com/image/info8/584b92a1c7aa4b018b4184c942d8e877.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/584b92a1c7aa4b018b4184c942d8e877.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第23张图片" width="650" height="286" style="border:1px solid black;"></a></p> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/8eabb26a9ea842109d5d95a3d1544a65.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/8eabb26a9ea842109d5d95a3d1544a65.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第24张图片" width="650" height="257" style="border:1px solid black;"></a></p> <p>此方法优点是js文件可以被很多页面使用,提高复用率。</p> <p>分析下列代码:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>js/js01.js<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token script"><span class="token language-javascript"> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"test"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>问题:会不会弹出test文字提示框?<br> 答:不会。<strong>当一个script标签一旦引用了外部的js文件,如果在这个标签还有js代码,是不会执行的。</strong></p> <p>分析下列代码:</p> <pre><code class="prism language-html"><span class="token doctype"><span class="token punctuation"><!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>cn<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>UTF-8<span class="token punctuation">"</span></span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>title</span><span class="token punctuation">></span></span>Document<span class="token tag"><span class="token tag"><span class="token punctuation"></</span>title</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>js/js01.js<span class="token punctuation">"</span></span><span class="token punctuation">></span></span><span class="token script"><span class="token language-javascript"> <span class="token comment">// alert("test");</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span><span class="token punctuation">></span></span><span class="token script"><span class="token language-javascript"> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"今天天气很好"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>head</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"><</span>script</span><span class="token punctuation">></span></span><span class="token script"><span class="token language-javascript"> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"今天心情很好"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </span></span><span class="token tag"><span class="token tag"><span class="token punctuation"></</span>script</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>body</span><span class="token punctuation">></span></span> <span class="token tag"><span class="token tag"><span class="token punctuation"></</span>html</span><span class="token punctuation">></span></span> </code></pre> <p>问题:会弹出什么提示框?<br> 答:首先执行外部链接的script语句,弹出“hello,world~”提示框。然后执行head标签的script语句,弹出“今天天气很好”提示框。最后执行body标签的script语句,弹出“今天心情很好”提示框。</p> <h4>3.2.2 JavaScript语法(重点)</h4> <p>1 js变量区分大小写。<br> 2 每一行的分号可有可无。<br> 3 标识符<br> 所谓标识符,就是指变量、函数、属性的名字,或者函数的参数。标识符可以是下列格式规则组合起来的一或多个字符:<br> 第一字符必须是一个字母、下划线或一个美元符号($)。<br> 其他字符可以是字母、下划线、美元符号或数字。<br> 不能把关键字、保留字、true、false和null作为标识符。<br> 例如:<br> myname,book123_,_123,$123都是合法的标识符。<br> 123,true,null,@123,abc!都不是合法的标识符。<br> 4 注释<br> 单行注释</p> <pre><code class="prism language-javascript"><span class="token comment">//注释</span> </code></pre> <p>多行注释</p> <pre><code class="prism language-javascript"><span class="token comment">/* 多 行 注 释 */</span> </code></pre> <p>注释的内容在代码执行过程中不起作用。<br> 5 定义变量时,使用var运算符。声明变量的格式:<code>var 变量名=值;</code><br> 比如:<br> var username=“tom”; 正确<br> var age=30; 正确</p> <p>6 使用大括号标签代码块<br> {}被封装在大括号内的语句按照顺序执行。</p> <pre><code class="prism language-javascript"><span class="token punctuation">{</span> 语句块<span class="token number">1</span><span class="token punctuation">;</span> 语句块<span class="token number">2</span><span class="token punctuation">;</span> 语句块<span class="token number">3</span><span class="token punctuation">;</span> <span class="token comment">//依次执行语句块1,语句块2,语句块3</span> <span class="token punctuation">}</span> </code></pre> <p>7 JavaScript中的关键字<br> 关键字不能用作变量名。函数名以及循环标签。<br> 关键字有如下:</p> <pre><code class="prism language-javascript">abstract <span class="token keyword">continue</span> finally <span class="token keyword">instanceof</span> <span class="token class-name">private</span> <span class="token keyword">this</span> boolean <span class="token keyword">default</span> float int <span class="token keyword">public</span> <span class="token keyword">throw</span> <span class="token keyword">break</span> <span class="token keyword">do</span> <span class="token keyword">for</span> <span class="token keyword">interface</span> <span class="token class-name">return</span> <span class="token keyword">typeof</span> byte double <span class="token keyword">function</span> long short <span class="token boolean">true</span> <span class="token keyword">case</span> <span class="token keyword">else</span> goto native <span class="token keyword">static</span> <span class="token keyword">var</span> catch <span class="token keyword">extends</span> <span class="token class-name">implements</span> <span class="token keyword">new</span> <span class="token class-name">super</span> <span class="token keyword">void</span> char <span class="token boolean">false</span> <span class="token keyword">import</span> <span class="token keyword">null</span> <span class="token keyword">switch</span> <span class="token keyword">while</span> <span class="token keyword">class</span> <span class="token class-name">final</span> <span class="token keyword">in</span> <span class="token keyword">package</span> <span class="token keyword">with</span> synchronized </code></pre> <h4>3.2.3 JavaScript的数据类型</h4> <p>(1)数值型有整型和浮点型<br> 整型</p> <pre><code class="prism language-javascript"><span class="token number">123</span> <span class="token comment">//十进制</span> <span class="token number">0123</span> <span class="token comment">//八进制,以0开头</span> <span class="token number">0x123</span><span class="token comment">//十六进制,以0x开头</span> </code></pre> <p>浮点型<br> 整数部分假小数部分组成,只能用十进制表示,不过可以使用科学记数法。</p> <pre><code class="prism language-javascript"><span class="token number">3.1415926</span><span class="token comment">//标准形式的浮点数</span> <span class="token number">3.14E9</span><span class="token comment">//采用可惜记数法来表示,等于3.14*10^9</span> </code></pre> <p>如下例子:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x<span class="token operator">=</span><span class="token number">123</span><span class="token punctuation">;</span> <span class="token keyword">var</span> y<span class="token operator">=</span><span class="token number">123.4567</span><span class="token punctuation">;</span> <span class="token keyword">var</span> z<span class="token operator">=</span><span class="token number">3.14E2</span><span class="token punctuation">;</span> </code></pre> <p>(2)字符串型<br> 字符串型数据是使用单引号或者双引号括起来的一个或者多个字符。</p> <pre><code class="prism language-javascript"><span class="token string">'a'</span> <span class="token string">'Hello World'</span> <span class="token string">"a"</span> <span class="token string">"Hello World"</span> </code></pre> <p>JavaScript与Java不一样,js没有char数据类型,如果要表示单个字符,必须使用长度为1的字符串。<br> 单引号包含双引号:<code>'大家好,我叫"tom""</code><br> 双引号包含单引号:<code>"大家好,我叫'tom'"</code><br> 如下例子:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token string">"test"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> b<span class="token operator">=</span><span class="token string">'testing'</span><span class="token punctuation">;</span> </code></pre> <p>(3)布尔型<br> 布尔型数据只有true或者false。在js中也可以使用整数0代表false,使用非0的整<br> 数来代表true。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> m<span class="token operator">=</span><span class="token boolean">true</span><span class="token punctuation">;</span> <span class="token keyword">var</span> bor<span class="token operator">=</span><span class="token boolean">false</span><span class="token punctuation">;</span> <span class="token keyword">var</span> ye<span class="token operator">=</span><span class="token number">7</span><span class="token operator">></span><span class="token number">1</span><span class="token punctuation">;</span><span class="token comment">//ye的值为true</span> </code></pre> <p>(4)转义字符<br> 以反斜杠开头的不可显示的特殊字符通常称为控制字符,也被称为转义字符。</p> <pre><code class="prism language-javascript">\b <span class="token comment">//退格</span> \n <span class="token comment">//换行</span> \t <span class="token comment">//Tab符</span> \r <span class="token comment">//回车符</span> \' <span class="token comment">//单引号</span> \" <span class="token comment">//双引号</span> \\ <span class="token comment">//反斜杠</span> </code></pre> <p>js文件如下:</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"hello,world~\n ab\tc\n a\rbc\n a\'b\"c\\"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>运行效果如下图:<br> <a href="http://img.e-com-net.com/image/info8/b331ca31beaa4669bb3bf15163aaa7b7.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/b331ca31beaa4669bb3bf15163aaa7b7.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第25张图片" width="650" height="347" style="border:1px solid black;"></a><br> (5)空值<br> null,用于定义空的或者不存在的引用。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token keyword">null</span><span class="token punctuation">;</span> </code></pre> <p>(6)未定义值<br> 已经声明但是没有赋值的的变量。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token comment">//undefined 是关键字,用来代表未定义值</span> </code></pre> <p>注:<br> 查看一个数据类型的格式</p> <pre><code class="prism language-javascript"><span class="token keyword">typeof</span><span class="token punctuation">(</span>变量名<span class="token punctuation">)</span> <span class="token comment">//格式一</span> type 变量名 <span class="token comment">//格式二</span> </code></pre> <pre><code class="prism language-javascript"><span class="token keyword">var</span> n<span class="token operator">=</span><span class="token string">"大家好,我是‘叶大叔’"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> m<span class="token operator">=</span><span class="token boolean">true</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token keyword">typeof</span><span class="token punctuation">(</span>n<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token keyword">typeof</span> m<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>运行效果如下图:<br> <a href="http://img.e-com-net.com/image/info8/2b124a945c644c2db3f3e67583281252.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/2b124a945c644c2db3f3e67583281252.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第26张图片" width="650" height="253" style="border:1px solid black;"></a><br> <a href="http://img.e-com-net.com/image/info8/6e720e080d7d47ba85311a8393ef68ba.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/6e720e080d7d47ba85311a8393ef68ba.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第27张图片" width="650" height="265" style="border:1px solid black;"></a></p> <h4>3.2.4 变量的定义与使用</h4> <p>(1)变量的命名规则<br> 与标识符规则一致!因为变量是标识符的一种。<br> (2)变量的声明</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> variable<span class="token punctuation">;</span> </code></pre> <p>可以使用一个var声明多个变量,比如</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token punctuation">,</span>b<span class="token punctuation">,</span>c<span class="token punctuation">,</span>d<span class="token punctuation">;</span> </code></pre> <p>可以在声明变量的同时对它进行赋值,也就是初始化。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">,</span>b<span class="token operator">=</span><span class="token boolean">true</span><span class="token punctuation">,</span>c<span class="token operator">=</span><span class="token string">"123"</span><span class="token punctuation">,</span>d<span class="token operator">=</span><span class="token number">3.14</span><span class="token punctuation">;</span> </code></pre> <p>如果只是声明了变量,没有赋值,那么该变量的默认值是undefined。<br> JavaScript是弱类型,声明的时候不需要指定变量的类型,变量的类型将根据变量的值来确定。</p> <p>函数就是方法,为了解决问题。也可以称为功能。</p> <pre><code class="prism language-javascript"><span class="token keyword">function</span> <span class="token function">函数名</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">{</span> 函数体<span class="token punctuation">;</span> <span class="token punctuation">}</span> </code></pre> <p>(3)全局变量的声明<br> 在函数体外声明的都是全局变量。<br> 在函数体内部不使用var声明直接赋值的变量是全局变量。??自己验证时出错,在函数内定义全局变量,无法引用该全局变量。</p> <p>(4)变量的作用域<br> 变量的作用域是指变量在程序中的有效范围。<br> 全局变量:定义在所有函数之外,作用于整个代码的变量。<br> 局部变量:定义在函数体内,只作用于函数体内的变量。</p> <h4>3.2.5 赋值运算符</h4> <pre><code class="prism language-javascript"><span class="token keyword">var</span> suername<span class="token operator">=</span><span class="token string">"Bass"</span><span class="token punctuation">;</span> <span class="token comment">//简单赋值</span> a<span class="token operator">+=</span>b<span class="token punctuation">;</span> <span class="token comment">//a=a+b;</span> a<span class="token operator">-=</span>b<span class="token punctuation">;</span><span class="token comment">//a=a-b;</span> a<span class="token operator">*=</span>b<span class="token punctuation">;</span> <span class="token comment">//a=a*b;</span> a<span class="token operator">/=</span>b<span class="token punctuation">;</span> <span class="token comment">//a=a/b;</span> a<span class="token operator">%=</span>b<span class="token punctuation">;</span> <span class="token comment">//a=a%b; 取余数</span> a<span class="token operator">&=</span>b<span class="token punctuation">;</span> <span class="token comment">//a=a&b; 且</span> a<span class="token operator">|=</span>b<span class="token punctuation">;</span> <span class="token comment">//a=a|b; 或</span> a<span class="token operator">^=</span>b<span class="token punctuation">;</span> <span class="token comment">//a=a^b; 异或</span> </code></pre> <pre><code class="prism language-javascript"><span class="token operator">&</span> <span class="token operator">|</span> <span class="token operator">^</span> <span class="token function">计算两个布尔值</span><span class="token punctuation">(</span><span class="token boolean">true</span><span class="token punctuation">,</span><span class="token boolean">false</span><span class="token punctuation">)</span> <span class="token operator">&</span> 一假全为假 <span class="token operator">|</span> 一真全为真 <span class="token operator">^</span> 不相同为真,相同为假 </code></pre> <p>&,例子如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token boolean">true</span><span class="token punctuation">;</span> <span class="token keyword">var</span> b<span class="token operator">=</span><span class="token boolean">false</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>a<span class="token operator">&</span>b<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/21cc8943f78b443c964bc4854eaa166d.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/21cc8943f78b443c964bc4854eaa166d.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第28张图片" width="650" height="269" style="border:1px solid black;"></a><br> 结果是false,0表示false。<br> |,例子如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token boolean">true</span><span class="token punctuation">;</span> <span class="token keyword">var</span> b<span class="token operator">=</span><span class="token boolean">false</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>a<span class="token operator">|</span>b<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/bd52c7150a9941d09bd8cf3bceeb1d69.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/bd52c7150a9941d09bd8cf3bceeb1d69.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第29张图片" width="650" height="267" style="border:1px solid black;"></a><br> 结果是true,1表示true。</p> <p>^,例子如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token boolean">true</span><span class="token punctuation">;</span> <span class="token keyword">var</span> b<span class="token operator">=</span><span class="token boolean">false</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>a<span class="token operator">^</span>b<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/2ec774f7cc524ce38bae53fca6f41757.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/2ec774f7cc524ce38bae53fca6f41757.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第30张图片" width="650" height="277" style="border:1px solid black;"></a><br> 结果是true,1表示true。</p> <p>此外还有自增和自减。</p> <pre><code class="prism language-javascript">i<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">;</span>j<span class="token operator">=</span><span class="token operator">++</span>i<span class="token punctuation">;</span> <span class="token comment">//j=2,i=2,++i是先加后用</span> i<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">;</span>j<span class="token operator">=</span>i<span class="token operator">++</span><span class="token punctuation">;</span> <span class="token comment">//j=2,i=1,i++是先用后加</span> i<span class="token operator">=</span><span class="token number">10</span><span class="token punctuation">;</span>j<span class="token operator">=</span><span class="token operator">--</span>i<span class="token punctuation">;</span> <span class="token comment">//j=9,i=9,--i是先减后用</span> i<span class="token operator">=</span><span class="token number">10</span><span class="token punctuation">;</span>j<span class="token operator">=</span>i<span class="token operator">--</span><span class="token punctuation">;</span> <span class="token comment">//i=10,j=9,i--是先用后减</span> <span class="token comment">//除法运算时,0不能作为除数,如果0是除数,则返回结果Intfinity。</span> </code></pre> <h3>3.3 JavaScript流程控制</h3> <p>JavaScript流程控制有if语句、switch语句、for语句、while语句和do-while语句。</p> <h4>3.3.1 if语句</h4> <pre><code class="prism language-javascript"><span class="token comment">//第一种</span> <span class="token keyword">if</span><span class="token punctuation">(</span>表达式<span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token punctuation">}</span> <span class="token comment">//第二种</span> <span class="token keyword">if</span><span class="token punctuation">(</span>表达式<span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token punctuation">}</span><span class="token keyword">else</span><span class="token punctuation">{</span> <span class="token punctuation">}</span> <span class="token comment">//第三种</span> <span class="token keyword">if</span><span class="token punctuation">(</span>表达式<span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token punctuation">}</span><span class="token keyword">else</span> <span class="token keyword">if</span><span class="token punctuation">(</span>表达式<span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token punctuation">}</span><span class="token keyword">else</span> <span class="token keyword">if</span><span class="token punctuation">(</span>表达式<span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token punctuation">}</span><span class="token keyword">else</span><span class="token punctuation">{</span> <span class="token punctuation">}</span> </code></pre> <p>例子如下:</p> <pre><code class="prism language-javascript"><span class="token comment">//第一种</span> <span class="token keyword">var</span> a<span class="token operator">=</span><span class="token number">20</span><span class="token punctuation">;</span> <span class="token keyword">if</span><span class="token punctuation">(</span>a<span class="token operator"><</span><span class="token number">50</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"条件成立"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token comment">//第二种</span> <span class="token keyword">var</span> a<span class="token operator">=</span><span class="token number">200</span><span class="token punctuation">;</span> <span class="token keyword">if</span><span class="token punctuation">(</span>a<span class="token operator"><</span><span class="token number">50</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"条件成立"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span><span class="token keyword">else</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"条件不成立"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token comment">//第三种</span> <span class="token comment">//分数[90,100]优秀,分数[60,90)及格,分数[0,60)不及格,其他为非法输入。</span> </code></pre> <h4>3.3.2 switch语句</h4> <p>switch语句的语法结构</p> <pre><code class="prism language-javascript"><span class="token keyword">switch</span><span class="token punctuation">(</span>表达式<span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token keyword">case</span> <span class="token number">1</span><span class="token operator">:</span>语句块<span class="token number">1</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token number">2</span><span class="token operator">:</span>语句块<span class="token number">2</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token number">3</span><span class="token operator">:</span>语句块<span class="token number">3</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> …… <span class="token keyword">default</span><span class="token operator">:</span>语句块n<span class="token punctuation">;</span> <span class="token punctuation">}</span> </code></pre> <p>break作用强制退出流程。<br> 例子如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> day<span class="token operator">=</span><span class="token string">"5"</span><span class="token punctuation">;</span> <span class="token keyword">switch</span><span class="token punctuation">(</span>day<span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token keyword">case</span> <span class="token string">"1"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期一"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"2"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期二"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"3"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期三"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"4"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期四"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"5"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期五"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"6"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期六"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"7"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期日"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">default</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"请输入合法数据"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> </code></pre> <p>结果会弹出“星期五”的提示框。<br> 如果改写上述例子,删除一些break,如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> day<span class="token operator">=</span><span class="token string">"5"</span><span class="token punctuation">;</span> <span class="token keyword">switch</span><span class="token punctuation">(</span>day<span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token keyword">case</span> <span class="token string">"1"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期一"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"2"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期二"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"3"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期三"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"4"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期四"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token keyword">break</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"5"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期五"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"6"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期六"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">case</span> <span class="token string">"7"</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"星期日"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">default</span><span class="token operator">:</span><span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"请输入合法数据"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> </code></pre> <p>会弹出“星期五”、“星期六”、“星期日”和“请输入合法数据”的提示框。如果字啊语句块后面没有break语句,switch则会一直执行下去。</p> <h4>3.3.3 for语句</h4> <p>语法格式:<br> for(①initialize;②test;④increment){<br> ③statement<br> }<br> ①->②(true)->③->④->②(true)->③->④->…<br> ①->②(true)->③->④->②(false) for循环结束<br> 例子如下:</p> <pre><code class="prism language-javascript"><span class="token comment">//求1-10整数和。</span> <span class="token keyword">var</span> sum<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span> <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">var</span> i<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">;</span>i<span class="token operator"><=</span><span class="token number">10</span><span class="token punctuation">;</span>i<span class="token operator">++</span><span class="token punctuation">)</span><span class="token punctuation">{</span> sum<span class="token operator">=</span>sum<span class="token operator">+</span>i<span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"1-10的整数和为"</span><span class="token operator">+</span>sum<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <h4>3.3.4 while语句</h4> <p>语法格式:while(①expression){<br> ②statement<br> }<br> ①(true)->②->①(true)->②…①(false)直接退出while循环。</p> <pre><code class="prism language-javascript"><span class="token comment">//用while语句求1-10整数和</span> <span class="token keyword">var</span> sum<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span> <span class="token keyword">var</span> i<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">;</span> <span class="token keyword">while</span><span class="token punctuation">(</span>i<span class="token operator"><=</span><span class="token number">10</span><span class="token punctuation">)</span><span class="token punctuation">{</span> sum<span class="token operator">=</span>sum<span class="token operator">+</span>i<span class="token punctuation">;</span> i<span class="token operator">++</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"1-10的整数和为"</span><span class="token operator">+</span>sum<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <h4>3.3.5 do-while语句</h4> <p>语法格式:do{<br> ①statement<br> }while(②expression);</p> <pre><code class="prism language-javascript"><span class="token comment">//用do-while语句求1-10整数和</span> <span class="token keyword">var</span> sum<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span> <span class="token keyword">var</span> i<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">;</span> <span class="token keyword">do</span><span class="token punctuation">{</span> sum<span class="token operator">=</span>sum<span class="token operator">+</span>i<span class="token punctuation">;</span> i<span class="token operator">++</span><span class="token punctuation">;</span> <span class="token punctuation">}</span><span class="token keyword">while</span><span class="token punctuation">(</span>i<span class="token operator"><=</span><span class="token number">10</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"1-10的整数和为"</span><span class="token operator">+</span>sum<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>while循环是先判断条件是否成立,然后再根据判断的结果是否执行循环体。也就是说循环体有可能一次都执行不了。<br> do-while循环是先执行一次循环体,然后再判断条件是否成立。所以不管条件是否成立,至少能够执行一次。</p> <h3>3.4 函数</h3> <p>函数就是方法,解决某个问题,实现某个功能。</p> <h4>3.4.1 函数的定义</h4> <p>function 函数名字([参数1,参数2,参数3,……]){<br> 函数体;<br> [return 返回值;]<br> }<br> 注:[ ]为可选项。<br> 例如:定义两数相乘的函数,如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">function</span> <span class="token function">multiplication</span><span class="token punctuation">(</span><span class="token parameter">x<span class="token punctuation">,</span>y</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token keyword">var</span> result<span class="token operator">=</span>x<span class="token operator">*</span>y<span class="token punctuation">;</span> <span class="token keyword">return</span> result<span class="token punctuation">;</span> <span class="token punctuation">}</span> </code></pre> <h4>3.4.2 函数的调用</h4> <p>格式:函数名 (实参);<br> 例如:调用multiplication函数,实参为3,4,如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token function">multiplication</span><span class="token punctuation">(</span><span class="token number">3</span><span class="token punctuation">,</span><span class="token number">4</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"相乘结果为"</span><span class="token operator">+</span>a<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/0ecc8a0cb8564493aeb76f0db6d4be90.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/0ecc8a0cb8564493aeb76f0db6d4be90.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第31张图片" width="650" height="287" style="border:1px solid black;"></a></p> <h4>3.4.3 匿名函数</h4> <p>作用:用一个变量来接收函数。<br> 格式:<br> var 变量名=function([参数1,参数2,参数3,……]){<br> 函数体;<br> [return 返回值;]<br> }</p> <p>匿名函数例子,如下:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> <span class="token function-variable function">a</span><span class="token operator">=</span><span class="token keyword">function</span><span class="token punctuation">(</span><span class="token parameter">x<span class="token punctuation">,</span>y</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token keyword">var</span> z<span class="token operator">=</span>x<span class="token operator">+</span>y<span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"z的值为"</span><span class="token operator">+</span>z<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token function">a</span><span class="token punctuation">(</span><span class="token number">3</span><span class="token punctuation">,</span><span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>运行结果如下:<br> <a href="http://img.e-com-net.com/image/info8/5bb7edad9a924cd5aa4276c4ebd3d057.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/5bb7edad9a924cd5aa4276c4ebd3d057.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第32张图片" width="637" height="278" style="border:1px solid black;"></a></p> <h4>3.4.4 全局函数</h4> <p>全局函数不属于任何一个对象,直接写名称使用即可。<br> (1)encodeURI函数<br> 作用:对字符进行编码</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> str<span class="token operator">=</span><span class="token string">"测试testing123!"</span> <span class="token keyword">var</span> encode01<span class="token operator">=</span><span class="token function">encodeURI</span><span class="token punctuation">(</span>str<span class="token punctuation">)</span><span class="token punctuation">;</span> document<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>encode01<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>运行效果如下图:<br> <a href="http://img.e-com-net.com/image/info8/0b21c5cb5aa945c987fea0a5bc306851.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/0b21c5cb5aa945c987fea0a5bc306851.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第33张图片" width="553" height="244" style="border:1px solid black;"></a><br> 所以,“测试”的编码为%E6%B5%8B%E8%AF%95。</p> <p>(2)decodeURI函数<br> 作用:对字符进行解码</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> str<span class="token operator">=</span><span class="token string">"%E6%B5%8B%E8%AF%95"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> decode01<span class="token operator">=</span><span class="token function">decodeURI</span><span class="token punctuation">(</span>str<span class="token punctuation">)</span><span class="token punctuation">;</span> document<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>decode01<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>运行效果如下图:<br> <a href="http://img.e-com-net.com/image/info8/e70e4a7a1e3a4633be35b3acfa289636.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/e70e4a7a1e3a4633be35b3acfa289636.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第34张图片" width="534" height="246" style="border:1px solid black;"></a><br> 所以,%E6%B5%8B%E8%AF%95解码为“测试”。</p> <p>(3)encodeURIComponent函数<br> 作用:对URI组件进行编码。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> uri <span class="token operator">=</span> <span class="token string">"https://w3school.com.cn/my test.asp?name=ståle&car=saab"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> res <span class="token operator">=</span> <span class="token function">encodeURIComponent</span><span class="token punctuation">(</span>uri<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>res<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/f0838eec77bb472ba7a222d43507595f.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/f0838eec77bb472ba7a222d43507595f.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第35张图片" width="650" height="309" style="border:1px solid black;"></a></p> <p>(4)decodeURIComponent函数<br> 作用:解码 URI 组件。<br> 语法:decodeURIComponent(uri)<br> uri参数为必须参数,为要解码的URI。<br> 返回值:字符串,表示解码后的 URI。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> uri<span class="token operator">=</span><span class="token string">"https%3A%2F%2Fw3school.com.cn%2Fmy%20test.asp%3Fname%3Dst%C3%A5le%26car%3Dsaab"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> rui_dec<span class="token operator">=</span><span class="token function">decodeURIComponent</span><span class="token punctuation">(</span>uri<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>rui_dec<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p><a href="http://img.e-com-net.com/image/info8/59ae3b2649844135bdc65402acd0f426.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/59ae3b2649844135bdc65402acd0f426.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第36张图片" width="650" height="299" style="border:1px solid black;"></a><br> 该结果就是上题的uri。</p> <p>(5)eval函数<br> 作用:识别字符串中的js代码</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> str<span class="token operator">=</span><span class="token string">"alert('123')"</span><span class="token punctuation">;</span><span class="token comment">//字符串为alert('123')</span> <span class="token function">eval</span><span class="token punctuation">(</span>str<span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token comment">//eval函数识别字符串中的js代码</span> document<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span><span class="token string">"<hr>"</span><span class="token punctuation">)</span><span class="token punctuation">;</span><span class="token comment">//在页面中显示一条水平线,hr标签为显示为一条水平线</span> </code></pre> <p>运行效果如下图:<br> <a href="http://img.e-com-net.com/image/info8/914fd0e76340455b97bed2ec82d136ce.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/914fd0e76340455b97bed2ec82d136ce.jpg" alt="软件测试 Web自动化测试 基础知识 HTML CSS JavaScript_第37张图片" width="650" height="249" style="border:1px solid black;"></a></p> <p><a href="http://img.e-com-net.com/image/info8/4dc0917b3959405e9bb1e638cadd7d5e.jpg" target="_blank"><img src="http://img.e-com-net.com/image/info8/4dc0917b3959405e9bb1e638cadd7d5e.jpg" alt="在这里插入图片描述" width="650" height="67"></a></p> <p>(6)isFinite函数<br> 作用:可确定数字是否是有限的合法数字。<br> 如果值为 +infinity、-infinity 或 NaN(非数字),则此函数返回 false,否则返回 true。<br> 返回值为布尔值。如果值为 +infinity、-infinity 或 NaN,则返回 false,否则返回 true。<br> 注:<br> JavaScript 全局属性</p> <table> <thead> <tr> <th>属性</th> <th>描述</th> </tr> </thead> <tbody> <tr> <td>Infinity</td> <td>表示正/负无穷大的数值</td> </tr> <tr> <td>NaN</td> <td>“非数字”(Not-aNumber)</td> </tr> <tr> <td>undefined</td> <td>表示变量尚未赋值</td> </tr> </tbody> </table> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">isFinite</span><span class="token punctuation">(</span><span class="token number">123</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回true,因为123是合法数字。如果输入NaN,NaN为非法字符,则返回false。</p> <p>(7)isNaN函数<br> 作用:确定值是否为非数字(Not-a-Number)<br> 不是数字返回true,是数字返回false</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> str<span class="token operator">=</span><span class="token string">'123'</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">isNaN</span><span class="token punctuation">(</span>str<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回为false。</p> <p>(8)Number函数<br> 作用:函数将对象参数转换为表示对象值的数字。</p> <p>语法:Number(object)<br> object 可选。JavaScript 对象。如果未提供该参数,则返回 0。</p> <p>返回值:数值。将不同的对象值返回为数字。<br> 如果该值无法转换为合法数字,则返回 NaN。如果未提供参数,则返回 0。<br> 如果参数是 Date 对象,则 Number() 函数返回自 UTC 1970 年 1 月 1 日午夜以来的毫秒数。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">Number</span><span class="token punctuation">(</span><span class="token boolean">true</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回为1。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">Number</span><span class="token punctuation">(</span><span class="token boolean">false</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代运行码结果返回为0。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Date</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">Number</span><span class="token punctuation">(</span>x<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回自 UTC 1970 年 1 月 1 日午夜以来的毫秒数。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">Number</span><span class="token punctuation">(</span><span class="token string">"999"</span><span class="token punctuation">)</span><span class="token punctuation">)</span> </code></pre> <p>上述代码运行结果返回999数值。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">Number</span><span class="token punctuation">(</span><span class="token string">"999 888"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回NaN,999 888无法转换为合法数字。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">Number</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回0,未提供参数,则返回 0。</p> <p>(9)parseFloat函数<br> 作用:解析字符串并返回浮点数。<br> 此函数确定指定字符串中的第一个字符是否为数字。如果是,它会解析字符串直到到达数字的末尾,<strong>并将数字作为数字而不是字符串返回</strong>。<br> 注意:<br> 只返回字符串中的第一个数字!<br> 允许前导和尾随空格。<br> 如果第一个字符不能转换为数字,parseFloat() 返回 NaN。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">parseFloat</span><span class="token punctuation">(</span><span class="token string">"10"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回数值10。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">parseFloat</span><span class="token punctuation">(</span><span class="token string">"10.00"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回数值10。若小数后为0,则省略小数位。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">parseFloat</span><span class="token punctuation">(</span><span class="token string">"34 56 78"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回数值34。parseFloat函数只返回字符串中的第一个数字,即34。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">parseFloat</span><span class="token punctuation">(</span><span class="token string">" 60 "</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回数值60,parseFloat函数允许前导和尾随空格。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">parseFloat</span><span class="token punctuation">(</span><span class="token string">"40 years"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回数值40,parseFloat函数解析字符串直到到达数字的末尾,years不是数字,所以不能返回。</p> <pre><code class="prism language-javascript"><span class="token function">alert</span><span class="token punctuation">(</span><span class="token function">parseFloat</span><span class="token punctuation">(</span><span class="token string">"hello"</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果返回数值NaN,第一个字符不能转换为数字,parseFloat() 返回 NaN。</p> <p>(10)parselnt函数<br> 作用:函数解析字符串并返回整数。<br> parseInt(string,radix)<br> string 必需。要解析的字符串。如果第一个字符不能转换为数字,parseInt() 返回 NaN。<br> radix 可选参数。代表要使用的数字系统的数字(从 2 到 36)。<br> 如果 radix 参数被省略,JavaScript 假定如下:<br> 如果字符串以 “0x” 开头,则基数为 16(十六进制)<br> 如果字符串以 “0” 开头,则基数为 8(八进制)。此特性已弃用<br> 如果字符串以任何其他值开头,则基数为 10(十进制)<br> 返回值: 数值。如果第一个字符不能转换为数字,则返回 NaN。<br> <strong>注意:只返回字符串中的第一个数字!</strong></p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token function">parseInt</span><span class="token punctuation">(</span><span class="token string">"10"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果为10,说明parselnt函数函数解析字符串并返回整数。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a<span class="token operator">=</span><span class="token function">parseInt</span><span class="token punctuation">(</span><span class="token string">"hello"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果为返回值为NaN,第一个字符不能转换为数字,parselnt函数返回 NaN。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> a <span class="token operator">=</span> <span class="token function">parseInt</span><span class="token punctuation">(</span><span class="token string">"3 4 45 66"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码运行结果为3,说明只返回字符串中的第一个数字。</p> <p>(11)String函数<br> 作用:将对象的值转换为字符串。<br> 注释:String() 函数返回与单个对象的 toString() 相同的值。<br> 语法:String(object)<br> object 必需。JavaScript 对象。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x1 <span class="token operator">=</span> <span class="token function">Boolean</span><span class="token punctuation">(</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">var</span> res <span class="token operator">=</span><span class="token function">String</span><span class="token punctuation">(</span>x1<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>res<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码就行结果返回false。String函数将x1的值转为为字符串false。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x2 <span class="token operator">=</span> <span class="token function">Boolean</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">var</span> res <span class="token operator">=</span><span class="token function">String</span><span class="token punctuation">(</span>x2<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>res<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码就行结果返回true。String函数将x2的值转为为字符串true。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x3 <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Date</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">var</span> res <span class="token operator">=</span><span class="token function">String</span><span class="token punctuation">(</span>x3<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>res<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码就行结果返回Fri Apr 01 2022 21:31:26 GMT+0800 (中国标准时间)。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x4 <span class="token operator">=</span> <span class="token string">"12345"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> res <span class="token operator">=</span><span class="token function">String</span><span class="token punctuation">(</span>x4<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>res<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码就行结果返回字符串12345。</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x5 <span class="token operator">=</span> <span class="token number">12345</span><span class="token punctuation">;</span> <span class="token keyword">var</span> res <span class="token operator">=</span><span class="token function">String</span><span class="token punctuation">(</span>x5<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token function">alert</span><span class="token punctuation">(</span>res<span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>上述代码就行结果返回字符串12345,String函数将整型12345转换为字符串12345。</p> <h3>3.5 事件</h3> <p>当在 HTML 页面中使用 JavaScript 时,JavaScript 能够“应对”这些事件。</p> <h4>3.5.1 常见的事件</h4> <table> <thead> <tr> <th>事件</th> <th>描述</th> </tr> </thead> <tbody> <tr> <td>onabort</td> <td>对象载入被中断时触发</td> </tr> <tr> <td>onablur</td> <td>元素或窗口本身失去焦点时触发</td> </tr> <tr> <td>onchange</td> <td>改变<code><select></code>元素中的选项或其他表单元素失去焦点,并且在其获取焦点后内容发生过改变时触发</td> </tr> <tr> <td>onerror</td> <td>出现错误时触发</td> </tr> <tr> <td>onfocus</td> <td>任何元素或窗口本身获得焦点时触发</td> </tr> <tr> <td>onkeydown</td> <td>键盘键(包括Shift、Alt等)被按下时触发</td> </tr> <tr> <td>onkeypress</td> <td>键盘被按下,并生成一个字符时触发。也就是说按下Shift或Alt等键不会触发</td> </tr> <tr> <td>onkeyup</td> <td>释放键盘上的按键时触发</td> </tr> <tr> <td>onload</td> <td>页面完全载入后触发</td> </tr> <tr> <td>onclick</td> <td>页面完全卸载后触发</td> </tr> <tr> <td>onclick</td> <td>单击鼠标邮件时触发。当光标的焦点在按钮上,并按Enter键是也会触发</td> </tr> <tr> <td>ondblclick</td> <td>双击鼠标左键时触发</td> </tr> <tr> <td>onmousedown</td> <td>单击任何一个鼠标按键时触发</td> </tr> <tr> <td>onmousemove</td> <td>鼠标在某个元素上移动时持续触发</td> </tr> <tr> <td>onmouseout</td> <td>鼠标从指定的元素上移开时触发</td> </tr> <tr> <td>onmouseover</td> <td>鼠标移动到某个元素时触发</td> </tr> <tr> <td>onmouseup</td> <td>释放任意一个鼠标按键时触发</td> </tr> <tr> <td>onrest</td> <td>单击充值按钮时,在<code><form></code>上触发</td> </tr> <tr> <td>onresize</td> <td>窗口或框架的大小发生改变时触发</td> </tr> <tr> <td>onscroll</td> <td>在任何带滚动条的元素或窗口上滚动时触发</td> </tr> <tr> <td>onselect</td> <td>选中文本时触发</td> </tr> <tr> <td>onsubmit</td> <td>单击提交按钮时,在<code><form></code>上触发</td> </tr> </tbody> </table> <h4>3.5.2 事件处理</h4> <p>时间出程序是用于响应某个时间而执行的处理程序。时间处理程序可以是任意的JavaScript语句,<strong>通常使用函数来对事件进行处理</strong>。<br> 第一种方式,事件处理在html中绑定:</p> <pre><code class="prism language-javascript"><span class="token operator"><</span><span class="token operator">!</span><span class="token constant">DOCTYPE</span> html<span class="token operator">></span> <span class="token operator"><</span>html lang<span class="token operator">=</span><span class="token string">"cn"</span><span class="token operator">></span> <span class="token operator"><</span>head<span class="token operator">></span> <span class="token operator"><</span>meta charset<span class="token operator">=</span><span class="token string">"UTF-8"</span><span class="token operator">></span> <span class="token operator"><</span>title<span class="token operator">></span>事件<span class="token operator"><</span><span class="token operator">/</span>title<span class="token operator">></span> <span class="token operator"><</span>script<span class="token operator">></span> <span class="token keyword">function</span> <span class="token function">save</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"按钮被点击"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token keyword">function</span> <span class="token function">fun</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"双击左键成功!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token operator"><</span><span class="token operator">/</span>script<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>head<span class="token operator">></span> <span class="token operator"><</span>body<span class="token operator">></span> <span class="token operator"><</span>input type<span class="token operator">=</span><span class="token string">"button"</span> value<span class="token operator">=</span><span class="token string">"按钮1"</span> onclick<span class="token operator">=</span><span class="token string">"save()"</span> <span class="token operator">></span> <span class="token operator"><</span>input type<span class="token operator">=</span><span class="token string">"button"</span> value<span class="token operator">=</span><span class="token string">"按钮2"</span> ondblclick<span class="token operator">=</span><span class="token string">"fun()"</span> <span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>body<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>html<span class="token operator">></span> </code></pre> <p>上述代码运行结果为:页面有两个按钮,一个按钮1,一个按钮2。鼠标左键单击按钮1,弹出“按钮被点击”窗口。鼠标左键双击按钮2,弹出“双击左键成功!”窗口。</p> <p>第二种方式,事件处理在JavaScript中绑定:</p> <pre><code class="prism language-javascript"><span class="token operator"><</span><span class="token operator">!</span><span class="token constant">DOCTYPE</span> html<span class="token operator">></span> <span class="token operator"><</span>html lang<span class="token operator">=</span><span class="token string">"cn"</span><span class="token operator">></span> <span class="token operator"><</span>head<span class="token operator">></span> <span class="token operator"><</span>meta charset<span class="token operator">=</span><span class="token string">"UTF-8"</span><span class="token operator">></span> <span class="token operator"><</span>title<span class="token operator">></span>Document<span class="token operator"><</span><span class="token operator">/</span>title<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>head<span class="token operator">></span> <span class="token operator"><</span>body<span class="token operator">></span> <span class="token operator"><</span>form<span class="token operator">></span> <span class="token operator"><</span>input type<span class="token operator">=</span><span class="token string">"button"</span> value<span class="token operator">=</span><span class="token string">"按钮"</span> id<span class="token operator">=</span><span class="token string">"btn"</span> <span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>form<span class="token operator">></span> <span class="token operator"><</span>script<span class="token operator">></span> <span class="token keyword">var</span> temp<span class="token operator">=</span>document<span class="token punctuation">.</span><span class="token function">getElementById</span><span class="token punctuation">(</span><span class="token string">"btn"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> temp<span class="token punctuation">.</span><span class="token function-variable function">onclick</span><span class="token operator">=</span><span class="token keyword">function</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"点击成功!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token operator"><</span><span class="token operator">/</span>script<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>body<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>html<span class="token operator">></span> </code></pre> <p>上述代码运行结果为:点击按钮,弹出“点击成功!”的提示框。</p> <h3>3.6 正则表达式</h3> <p>定义<br> 正则表达式是构成搜索模式的字符序列。该搜索模式可用于文本搜索和文本替换操作。<br> 当搜索文本中的数据时,您可使用搜索模式来描述您搜索的内容。<br> 正则表达式可以是单字符,或者更复杂的模式。<br> 正则表达式可用于执行所有类型的<strong>文本搜索</strong>和<strong>文本替换</strong>操作。</p> <p>语法</p> <pre><code class="prism language-javascript"><span class="token operator">/</span>pattern<span class="token operator">/</span>modifiers<span class="token punctuation">;</span> </code></pre> <p>例子</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> patt <span class="token operator">=</span> <span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">hello</span><span class="token regex-delimiter">/</span><span class="token regex-flags">i</span></span><span class="token punctuation">;</span> </code></pre> <p>例子解释:<br> /hello/i 是一个正则表达式。<br> hello是模式(pattern)(在搜索中使用)。<br> i 是修饰符(把搜索修改为大小写不敏感)。</p> <p>在字符串方法<strong>search()</strong> 中使用正则表达式</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> str <span class="token operator">=</span> <span class="token string">"hello"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> n <span class="token operator">=</span> str<span class="token punctuation">.</span><span class="token function">search</span><span class="token punctuation">(</span><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">o</span><span class="token regex-delimiter">/</span><span class="token regex-flags">i</span></span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>n 中的结果将是:4</p> <p>在字符串方法<strong>replace()</strong> 中使用正则表达式<br> 例子<br> 使用大小写不明的正则表达式以hello来替换字符串中的Bass:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> str <span class="token operator">=</span> <span class="token string">"Visit Bass"</span><span class="token punctuation">;</span> <span class="token keyword">var</span> res <span class="token operator">=</span> str<span class="token punctuation">.</span><span class="token function">replace</span><span class="token punctuation">(</span><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">hello</span><span class="token regex-delimiter">/</span><span class="token regex-flags">i</span></span><span class="token punctuation">,</span> <span class="token string">"Bass"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>res 的结果将是:</p> <pre><code class="prism language-javascript">Visit hello </code></pre> <p>正则表达式修饰符<br> 修饰符可用于大小写不敏感的更全局的搜素:</p> <table> <thead> <tr> <th>修饰符</th> <th>描述</th> </tr> </thead> <tbody> <tr> <td>i</td> <td>执行对大小写不敏感的匹配</td> </tr> <tr> <td>g</td> <td>执行全局匹配(查找所有匹配而非在找到第一个匹配后停止)</td> </tr> <tr> <td>m</td> <td>执行多行匹配</td> </tr> </tbody> </table> <p>正则表达式模式<br> 括号用于查找一定范围的字符串:</p> <table> <thead> <tr> <th>表达式</th> <th>描述</th> </tr> </thead> <tbody> <tr> <td>[abc]</td> <td></td> </tr> <tr> <td>[0-9]</td> <td></td> </tr> <tr> <td>`(x</td> <td>y)`</td> </tr> </tbody> </table> <p>元字符(Metacharacter)是拥有特殊含义的字符:</p> <table> <thead> <tr> <th>元字符</th> <th>描述</th> </tr> </thead> <tbody> <tr> <td>\d</td> <td>查找数字</td> </tr> <tr> <td>\s</td> <td>查找空白字符</td> </tr> <tr> <td>\b</td> <td>匹配单词边界</td> </tr> <tr> <td>\uxxxx</td> <td>查找以十六进制数 xxxx 规定的 Unicode 字符</td> </tr> </tbody> </table> <p>定义量词:</p> <table> <thead> <tr> <th>量词</th> <th>描述</th> </tr> </thead> <tbody> <tr> <td>n+</td> <td>匹配任何包含至少一个 n 的字符串</td> </tr> <tr> <td>n*</td> <td>匹配任何包含零个或多个 n 的字符串</td> </tr> <tr> <td>n?</td> <td>匹配任何包含零个或一个 n 的字符串</td> </tr> </tbody> </table> <p>使用 test()<br> test() 是一个正则表达式方法。<br> 它通过模式来搜索字符串,然后根据结果返回 true 或 false。</p> <p>例子</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> patt <span class="token operator">=</span> <span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">e</span><span class="token regex-delimiter">/</span></span><span class="token punctuation">;</span> patt<span class="token punctuation">.</span><span class="token function">test</span><span class="token punctuation">(</span><span class="token string">"The best things in life are free!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>由于字符串中有一个 “e”,以上代码的输出将是:</p> <pre><code class="prism language-javascript"><span class="token boolean">true</span> </code></pre> <p>上面的两行可缩短为一行:</p> <pre><code class="prism language-javascript"><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">e</span><span class="token regex-delimiter">/</span></span><span class="token punctuation">.</span><span class="token function">test</span><span class="token punctuation">(</span><span class="token string">"The best things in life are free!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>使用 exec()<br> exec()方法返回值不是true或者false。而是当没有搜索到匹配的字符时,返回null,否则<strong>返回一个数组</strong>,这个数组的第一个元素包含与正则表达式相匹配的字符串,其他元素包含的是<strong>匹配的各个分组</strong>(用括号括起来的子表达式)。</p> <p>例子</p> <pre><code class="prism language-javascript"><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">e</span><span class="token regex-delimiter">/</span></span><span class="token punctuation">.</span><span class="token function">exec</span><span class="token punctuation">(</span><span class="token string">"The best things in life are free!"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> </code></pre> <p>由于字符串中有一个 “e”,以上代码的输出将是:</p> <pre><code class="prism language-javascript">e </code></pre> <p>身份证例子</p> <pre><code class="prism language-javascript"><span class="token operator"><</span><span class="token operator">!</span><span class="token constant">DOCTYPE</span> html<span class="token operator">></span> <span class="token operator"><</span>html lang<span class="token operator">=</span><span class="token string">"cn"</span><span class="token operator">></span> <span class="token operator"><</span>head<span class="token operator">></span> <span class="token operator"><</span>meta charset<span class="token operator">=</span><span class="token string">"UTF-8"</span><span class="token operator">></span> <span class="token operator"><</span>title<span class="token operator">></span>Document<span class="token operator"><</span><span class="token operator">/</span>title<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>head<span class="token operator">></span> <span class="token operator"><</span>body<span class="token operator">></span> <span class="token operator"><</span>form name<span class="token operator">=</span><span class="token string">"f"</span><span class="token operator">></span> 身份证:<span class="token operator"><</span>input type<span class="token operator">=</span><span class="token string">"text"</span> name<span class="token operator">=</span><span class="token string">"id"</span> size<span class="token operator">=</span><span class="token string">"20"</span><span class="token operator">></span> <span class="token operator"><</span>input type<span class="token operator">=</span><span class="token string">"button"</span> value<span class="token operator">=</span><span class="token string">"提取"</span> onclick<span class="token operator">=</span><span class="token string">"grep()"</span><span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>form<span class="token operator">></span> <span class="token operator"><</span>script<span class="token operator">></span> <span class="token keyword">function</span> <span class="token function">grep</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token comment">//找到输入的身份证</span> <span class="token keyword">var</span> id_value<span class="token operator">=</span>f<span class="token punctuation">.</span>id<span class="token punctuation">.</span>value<span class="token punctuation">;</span> <span class="token comment">//声明身份证号的正则表达式</span> <span class="token keyword">var</span> pattern<span class="token operator">=</span><span class="token regex"><span class="token regex-delimiter">/</span><span class="token regex-source language-regex">(\d{6})(\d{8})(\d{4})</span><span class="token regex-delimiter">/</span></span><span class="token punctuation">;</span> <span class="token comment">//判定工作</span> <span class="token keyword">var</span> judge<span class="token operator">=</span>pattern<span class="token punctuation">.</span><span class="token function">exec</span><span class="token punctuation">(</span>id_value<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">if</span><span class="token punctuation">(</span>judge<span class="token operator">!=</span><span class="token keyword">null</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"出生日期"</span><span class="token operator">+</span>judge<span class="token punctuation">[</span><span class="token number">2</span><span class="token punctuation">]</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span><span class="token keyword">else</span><span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"请输入合法的身份证"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token punctuation">}</span> <span class="token operator"><</span><span class="token operator">/</span>script<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>body<span class="token operator">></span> <span class="token operator"><</span><span class="token operator">/</span>html<span class="token operator">></span> </code></pre> <p>将上述代码运行,在页面上的身份证文本框输入“441222199712121234”,弹出“出生日期19971212”提示框。</p> <h3>3.7 Cookies</h3> <p>Cookie 让您在网页中存储用户信息。<br> Cookie 是在您的计算机上存储在小的文本文件中的数据。<br> 当 web 服务器向浏览器发送网页后,连接被关闭,服务器会忘记用户的一切。<br> Cookie 是为了解决“如何记住用户信息”而发明的:<br> 当用户访问网页时,他的名字可以存储在 cookie 中。<br> 下次用户访问该页面时,cookie 会“记住”他的名字。</p> <p>Cookie 保存在<strong>名称值对</strong>中,如:</p> <pre><code class="prism language-javascript">username<span class="token operator">=</span>bass </code></pre> <p>当浏览器从服务器请求一个网页时,将属于该页的 cookie 添加到该请求中。这样服务器就获得了必要的数据来“记住”用户的信息。</p> <p>如果浏览器已关闭本地 cookie 支持,则以下实例均无法工作。</p> <h4>3.7.1 创建cookie</h4> <p>JavaScript 可以用 document.cookie 属性创建、读取、删除 cookie。<br> 通过 JavaScript,可以这样创建 cookie:</p> <pre><code class="prism language-javascript">doucument<span class="token punctuation">.</span>cookie<span class="token operator">=</span><span class="token string">"username=bass"</span><span class="token punctuation">;</span> </code></pre> <p>还可以添加有效日期(UTC 时间)。默认情况下,在浏览器关闭时会删除 cookie:</p> <pre><code class="prism language-javascript">document<span class="token punctuation">.</span>cookie <span class="token operator">=</span> <span class="token string">"username=bass; expires=Sat Apr 02 2022 22:32:29 UTC"</span><span class="token punctuation">;</span> </code></pre> <p>通过 path 参数,您可以告诉浏览器 cookie 属于什么路径。默认情况下,cookie 属于当前页。</p> <pre><code class="prism language-javascript">document<span class="token punctuation">.</span>cookie <span class="token operator">=</span> <span class="token string">"username=bass; expires=Sat Apr 02 2022 22:32:29 UTC"</span><span class="token punctuation">;</span>path<span class="token operator">=</span><span class="token operator">/</span>"<span class="token punctuation">;</span> </code></pre> <h4>3.7.2 读取 cookie</h4> <p>通过 JavaScript,可以这样读取 cookie:</p> <pre><code class="prism language-javascript"><span class="token keyword">var</span> x <span class="token operator">=</span> document<span class="token punctuation">.</span>cookie<span class="token punctuation">;</span> </code></pre> <h4>3.7.3 改变 cookie</h4> <p>通过使用 JavaScript,你可以像你创建 cookie 一样改变它:</p> <pre><code class="prism language-javascript">document<span class="token punctuation">.</span>cookie <span class="token operator">=</span> <span class="token string">"username=bass; expires=Sat Apr 02 1970 22:32:29 UTC"</span><span class="token punctuation">;</span>path<span class="token operator">=</span><span class="token operator">/</span>"<span class="token punctuation">;</span> </code></pre> <p>旧 cookie 被覆盖。</p> <h4>3.7.4 删除 cookie</h4> <p>删除 cookie 时不必指定 cookie 值。<br> 直接把 expires 参数设置为过去的日期即可:</p> <pre><code class="prism language-javascript">document<span class="token punctuation">.</span>cookie <span class="token operator">=</span> <span class="token string">"username=bass; expires=Sat Apr 02 2022 22:32:29 UTC"</span><span class="token punctuation">;</span>path<span class="token operator">=</span><span class="token operator">/</span>"<span class="token punctuation">;</span> </code></pre> <p>您应该定义 cookie 路径以确保删除正确的 cookie。<br> 如果你不指定路径,一些浏览器不会让你删除 cookie。</p> <h4>3.7.5 cookie 字符串</h4> <p>document.cookie 属性看起来像一个正常的文本字符串。但它不是。<br> 即使你向 document.cookie 写一份完整的 cookie 字符串,当再次读取时,你只能看到它的名称-值对。<br> 如果设置了新 cookie,则旧的 cookie 不会被覆盖。新的 Cookie 会被添加到 document.cookie,所以如果你读取 document.cookie,你得到的东西会像这样:</p> <pre><code class="prism language-javascript">cookie1 <span class="token operator">=</span> value<span class="token punctuation">;</span> cookie2 <span class="token operator">=</span> value<span class="token punctuation">;</span> </code></pre> <p>如果你想找到一个指定 cookie 的值,你必须编写 JavaScript 函数来搜索 cookie 字符串中的 cookie 值。<br> 这里需要结合下面的实例!!!!!!!!!!!!</p> <h4>3.7.6 JavaScript Cookie 实例</h4> <p>创建一个 cookie 来存储访问者的名称。<br> 访客第一次到达网页时,会要求他填写姓名。然后将该名称存储在 cookie 中。<br> 下次访客到达同一页时,他将收到一条欢迎消息。<br> 例如,我们将创建 3 个JavaScript函数:<br> (1)设置cookie的函数<br> (2)获取 cookie 的函数<br> (3)检测 cookie 的函数</p> <p>(1)设置cookie的函数<br> 创建一个函数,将访问者的名字存储在 cookie 变量中:</p> <pre><code class="prism language-javascript"><span class="token keyword">function</span> <span class="token function">setCookie</span><span class="token punctuation">(</span><span class="token parameter">cname<span class="token punctuation">,</span>cvalue<span class="token punctuation">,</span>exdays</span><span class="token punctuation">)</span><span class="token punctuation">{</span> <span class="token keyword">var</span> d<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Date</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> d<span class="token punctuation">.</span><span class="token function">setTime</span><span class="token punctuation">(</span>d<span class="token punctuation">.</span><span class="token function">getTime</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token punctuation">(</span>exdays<span class="token operator">*</span><span class="token number">24</span><span class="token operator">*</span><span class="token number">60</span><span class="token operator">*</span><span class="token number">60</span><span class="token operator">*</span><span class="token number">1000</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">var</span> expires<span class="token operator">=</span><span class="token string">"expires"</span><span class="token operator">+</span>d<span class="token punctuation">.</span><span class="token function">toUTCString</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span> document<span class="token punctuation">.</span>cookie<span class="token operator">=</span>cname<span class="token operator">+</span><span class="token string">"="</span><span class="token operator">+</span>cvalue<span class="token operator">+</span><span class="token string">";"</span><span class="token operator">+</span>expires<span class="token operator">+</span><span class="token string">";path=/"</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> </code></pre> <p>分析上述代码,<br> cookie 的名字(cname),cookie 的值(cvalue),以及知道 cookie 过期的天数(exdays)。<br> 通过把 cookie 名称、cookie 值和过期字符串相加,该函数就设置了 cookie。</p> <p>(2)获取 cookie 的函数<br> 创建一个函数返回指定 cookie 的值:</p> <pre><code class="prism language-javascript"><span class="token keyword">function</span> <span class="token function">getCookie</span><span class="token punctuation">(</span><span class="token parameter">cname</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">var</span> name <span class="token operator">=</span> cname <span class="token operator">+</span> <span class="token string">"="</span><span class="token punctuation">;</span> <span class="token keyword">var</span> decodedCookie <span class="token operator">=</span> <span class="token function">decodeURIComponent</span><span class="token punctuation">(</span>document<span class="token punctuation">.</span>cookie<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">var</span> ca <span class="token operator">=</span> decodedCookie<span class="token punctuation">.</span><span class="token function">split</span><span class="token punctuation">(</span><span class="token string">';'</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">var</span> i <span class="token operator">=</span> <span class="token number">0</span><span class="token punctuation">;</span> i <span class="token operator"><</span>ca<span class="token punctuation">.</span>length<span class="token punctuation">;</span> i<span class="token operator">++</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">var</span> c <span class="token operator">=</span> ca<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token punctuation">;</span> <span class="token keyword">while</span> <span class="token punctuation">(</span>c<span class="token punctuation">.</span><span class="token function">charAt</span><span class="token punctuation">(</span><span class="token number">0</span><span class="token punctuation">)</span> <span class="token operator">==</span> <span class="token string">' '</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> c <span class="token operator">=</span> c<span class="token punctuation">.</span><span class="token function">substring</span><span class="token punctuation">(</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token keyword">if</span> <span class="token punctuation">(</span>c<span class="token punctuation">.</span><span class="token function">indexOf</span><span class="token punctuation">(</span>name<span class="token punctuation">)</span> <span class="token operator">==</span> <span class="token number">0</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">return</span> c<span class="token punctuation">.</span><span class="token function">substring</span><span class="token punctuation">(</span>name<span class="token punctuation">.</span>length<span class="token punctuation">,</span> c<span class="token punctuation">.</span>length<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token punctuation">}</span> <span class="token keyword">return</span> <span class="token string">""</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> </code></pre> <p>分析上述代码,把 cookie 作为参数(cname)。<br> 创建变量(name)与要搜索的文本(CNAME”=”)。<br> 解码 cookie 字符串,处理带有特殊字符的 cookie,例如 “$”。<br> 用分号把 document.cookie 拆分到名为 ca(decodedCookie.split(‘;’))的数组中。<br> 遍历 ca 数组(i = 0; i < ca.length; i++),然后读出每个值 c = ca[i]。<br> 如果找到 cookie(c.indexOf(name) == 0),则返回该 cookie 的值(c.substring(name.length, c.length)。<br> 如果未找到 cookie,则返回 “”。</p> <p>(3)检测 cookie 的函数<br> 我们创建检查 cookie 是否设置的函数。<br> 如果已设置 cookie,将显示一个问候。<br> 如果未设置 cookie,会显示一个提示框,询问用户的名字,并存储用户名 cookie 365 天,通过调用 setCookie 函数:</p> <pre><code class="prism language-javascript"><span class="token keyword">function</span> <span class="token function">checkCookie</span><span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token keyword">var</span> username <span class="token operator">=</span> <span class="token function">getCookie</span><span class="token punctuation">(</span><span class="token string">"username"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">if</span> <span class="token punctuation">(</span>username <span class="token operator">!=</span> <span class="token string">""</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token function">alert</span><span class="token punctuation">(</span><span class="token string">"Welcome again "</span> <span class="token operator">+</span> username<span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span> username <span class="token operator">=</span> <span class="token function">prompt</span><span class="token punctuation">(</span><span class="token string">"Please enter your name:"</span><span class="token punctuation">,</span> <span class="token string">""</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token keyword">if</span> <span class="token punctuation">(</span>username <span class="token operator">!=</span> <span class="token string">""</span> <span class="token operator">&&</span> username <span class="token operator">!=</span> <span class="token keyword">null</span><span class="token punctuation">)</span> <span class="token punctuation">{</span> <span class="token function">setCookie</span><span class="token punctuation">(</span><span class="token string">"username"</span><span class="token punctuation">,</span> username<span class="token punctuation">,</span> <span class="token number">365</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token punctuation">}</span> <span class="token punctuation">}</span> </code></pre> <h4>JavaScript小结</h4> <p>JavaScript是<strong>基于对象</strong>和<strong>事件驱动</strong>并具有相对安全性的<strong>客户端脚本语言</strong>。<br> JavaScript特点:松散型、解释型、基于对象、安全性、跨平台。<br> JavaScript可以写在html文件的head标签里面,可以写在body标签,也可以写在外部js文件。<br> JavaScript的数据类型有数值型、字符串型、布尔型、空值、未定义值。<br> 赋值运算符有+,-,*,/,%,&,|,^<br> JavaScript流程控制有if语句、switch语句、for语句、while语句和do-while语句。<br> 函数定义用function关键字定义。匿名函数用一个变量来接受函数,不用写函数名。<br> 全局函数可直接写名称使用即可。直接写名称使用即可。全局函数有encodeURI函数、decodeURI函数、encodeURIComponent函数、decodeURIComponent函数、eval函数、isFinite函数、isNaN函数、Number函数、parseFloat函数、parselnt函数、String函数。<br> JavaScript负责事件。通常使用函数来对事件进行处理。<br> 正则表达式是构成搜索模式的字符序列,简单理解为模板。<br> Cookie 是在您的计算机上存储在小的文本文件中的数据。对cookie操作有:操作cookie、读取cookie、改变cookie、删除cookie。</p> <h2>总结</h2> <p>html负责框架,css负责样式,js负责动作。</p> </div> </div> </div> </div> </div> <!--PC和WAP自适应版--> <div id="SOHUCS" sid="1512664982284730368"></div> <script type="text/javascript" src="/views/front/js/chanyan.js"></script> <!-- 文章页-底部 动态广告位 --> <div class="youdao-fixed-ad" id="detail_ad_bottom"></div> </div> <div class="col-md-3"> <div class="row" id="ad"> <!-- 文章页-右侧1 动态广告位 --> <div id="right-1" class="col-lg-12 col-md-12 col-sm-4 col-xs-4 ad"> <div class="youdao-fixed-ad" id="detail_ad_1"> </div> </div> <!-- 文章页-右侧2 动态广告位 --> <div id="right-2" class="col-lg-12 col-md-12 col-sm-4 col-xs-4 ad"> <div class="youdao-fixed-ad" id="detail_ad_2"></div> </div> <!-- 文章页-右侧3 动态广告位 --> <div id="right-3" class="col-lg-12 col-md-12 col-sm-4 col-xs-4 ad"> <div class="youdao-fixed-ad" id="detail_ad_3"></div> </div> </div> </div> </div> </div> </div> <div class="container"> <h4 class="pt20 mb15 mt0 border-top">你可能感兴趣的:(测试,前端开发,html5,css3,javascript,正则表达式)</h4> <div id="paradigm-article-related"> <div class="recommend-post mb30"> <ul class="widget-links"> <li><a href="/article/1943993028356141056.htm" title="有必要获得WHQL测试认证吗,有什么好处?" target="_blank">有必要获得WHQL测试认证吗,有什么好处?</a> <span class="text-muted"></span> <div>什么是WHQL认证?WHQL是MicrosoftWindowsHardwareQualityLab的缩写,中文意思是Windows硬件设备质量实验室,主要是对Windows操作系统的兼容性测试,检验硬件产品和驱动程序在windows系统下的兼容性和稳定性。当某一硬件或软件通过WHQL测试时,制造商可以在其产品包装和广告上使用“DesignedforWindows”标志。该标志可以证明硬件或软件已经</div> </li> <li><a href="/article/1943992396924645376.htm" title="WHQL签名怎么申请" target="_blank">WHQL签名怎么申请</a> <span class="text-muted">GDCA SSL证书</span> <a class="tag" taget="_blank" href="/search/windows/1.htm">windows</a> <div>WHQL(WindowsHardwareQualityLabs)签名是微软对硬件和驱动程序进行认证的一种方式,以确保它们与Windows操作系统的兼容性和稳定性。以下是申请WHQL签名的基本步骤,供您参考:1.准备阶段准备硬件设备和驱动程序:确保您的硬件设备已经准备好,并且对应的驱动程序已经经过充分的测试,能够在各种配置和环境下正常工作。获取EV代码签名证书:根据微软的要求,驱动程序进行WHQL认</div> </li> <li><a href="/article/1943992018892025856.htm" title="JSON 与 AJAX" target="_blank">JSON 与 AJAX</a> <span class="text-muted">Auscy</span> <a class="tag" taget="_blank" href="/search/json/1.htm">json</a><a class="tag" taget="_blank" href="/search/ajax/1.htm">ajax</a><a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF/1.htm">前端</a> <div>一、JSON(JavaScriptObjectNotation)1.数据类型与语法细节支持的数据类型:基本类型:字符串(需用双引号)、数字、布尔值(true/false)、null。复杂类型:数组([])、对象({})。严格语法规范:键名必须用双引号包裹(如"name":"张三")。数组元素用逗号分隔,最后一个元素后不能有多余逗号。数字不能以0开头(如012会被解析为12),不支持八进制/十六进制</div> </li> <li><a href="/article/1943990125864218624.htm" title="JavaScript 树形菜单总结" target="_blank">JavaScript 树形菜单总结</a> <span class="text-muted">Auscy</span> <a class="tag" taget="_blank" href="/search/microsoft/1.htm">microsoft</a> <div>树形菜单是前端开发中常见的交互组件,用于展示具有层级关系的数据(如文件目录、分类列表、组织架构等)。以下从核心概念、实现方式、常见功能及优化方向等方面进行总结。一、核心概念层级结构:数据以父子嵌套形式存在,如{id:1,children:[{id:2}]}。节点:树形结构的基本单元,包含自身信息及子节点(若有)。展开/折叠:子节点的显示与隐藏切换,是树形菜单的核心交互。递归渲染:因数据层级不固定,</div> </li> <li><a href="/article/1943987856808669184.htm" title="前端项目架构设计要领" target="_blank">前端项目架构设计要领</a> <span class="text-muted"></span> <div>1.架构设计的核心目标在设计前端项目架构时,核心目标是模块化、可维护、可扩展、可测试,以及开发效率的最大化。这些目标可以通过以下几个方面来实现:组件化:将UI功能封装为可复用的组件。模块化:将业务逻辑分解为独立的模块或服务。自动化构建与部署:实现自动化构建、测试和部署流程,减少人为操作的错误。代码规范化与检查:确保团队协作时,代码风格和质量一致。2.项目目录结构设计一个清晰合理的目录结构对大型项目</div> </li> <li><a href="/article/1943987101301272576.htm" title="精通Canvas:15款时钟特效代码实现指南" target="_blank">精通Canvas:15款时钟特效代码实现指南</a> <span class="text-muted">烟幕缭绕</span> <div>本文还有配套的精品资源,点击获取简介:HTML5的Canvas是一个用于绘制矢量图形的API,通过JavaScript实现动态效果。本项目集合了15种不同的时钟特效代码,帮助开发者通过学习绘制圆形、线条、时间更新、旋转、颜色样式设置及动画效果等概念,深化对Canvas的理解和应用。项目中的CSS文件负责时钟的样式设定,而JS文件则包含实现各种特效的逻辑,通过不同的函数或类处理时间更新和动画绘制,提</div> </li> <li><a href="/article/1943985463522029568.htm" title="Android 开源组件和第三方库汇总" target="_blank">Android 开源组件和第三方库汇总</a> <span class="text-muted">gyyzzr</span> <a class="tag" taget="_blank" href="/search/Android/1.htm">Android</a><a class="tag" taget="_blank" href="/search/Android/1.htm">Android</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E6%BA%90%E6%A1%86%E6%9E%B6/1.htm">开源框架</a> <div>转载1、github排名https://github.com/trending,github搜索:https://github.com/search2、https://github.com/wasabeef/awesome-android-ui目录UIUI卫星菜单节选器下拉刷新模糊效果HUD与Toast进度条UI其它动画网络相关响应式编程地图数据库图像浏览及处理视频音频处理测试及调试动态更新热更新</div> </li> <li><a href="/article/1943985462716723200.htm" title="docker-compose方式搭建lnmp环境——筑梦之路" target="_blank">docker-compose方式搭建lnmp环境——筑梦之路</a> <span class="text-muted">筑梦之路</span> <a class="tag" taget="_blank" href="/search/linux%E7%B3%BB%E7%BB%9F%E8%BF%90%E7%BB%B4/1.htm">linux系统运维</a><a class="tag" taget="_blank" href="/search/%E5%9B%BD%E4%BA%A7%E5%8C%96/1.htm">国产化</a><a class="tag" taget="_blank" href="/search/docker/1.htm">docker</a><a class="tag" taget="_blank" href="/search/android/1.htm">android</a><a class="tag" taget="_blank" href="/search/adb/1.htm">adb</a> <div>docker-compose.yml文件#生成docker-compose.ymlcat>docker-compose.ymlnginx/conf.d/default.conf">www/index.phpecho"开始启动服务..."docker-composeup-d#获取本机ipip_addr=$(hostname-I|awk'{print$1}')echo"部署完成!"echo"访问测试页</div> </li> <li><a href="/article/1943979785097113600.htm" title="【前端】jQuery数组合并去重方法总结" target="_blank">【前端】jQuery数组合并去重方法总结</a> <span class="text-muted"></span> <div>在jQuery中合并多个数组并去重,推荐使用原生JavaScript的Set对象(高效简单)或$.unique()(仅适用于DOM元素,不适用于普通数组)。以下是完整解决方案:方法1:使用ES6Set(推荐)//定义多个数组constarr1=[1,2,3];constarr2=[2,3,4];constarr3=[3,4,5];//合并数组并用Set去重constmergedArray=[...</div> </li> <li><a href="/article/1943974618851241984.htm" title="Vue3+Vite+TS+Axios整合详细教程" target="_blank">Vue3+Vite+TS+Axios整合详细教程</a> <span class="text-muted">老马聊技术</span> <a class="tag" taget="_blank" href="/search/Vue/1.htm">Vue</a><a class="tag" taget="_blank" href="/search/Vite/1.htm">Vite</a><a class="tag" taget="_blank" href="/search/TS/1.htm">TS</a><a class="tag" taget="_blank" href="/search/vue.js/1.htm">vue.js</a> <div>1.Vite简介Vite是新一代的前端构建工具,在尤雨溪开发Vue3.0的时候诞生。类似于Webpack+Webpack-dev-server。其主要利用浏览器ESM特性导入组织代码,在服务器端按需编译返回,完全跳过了打包这个概念,服务器随起随用。生产中利用Rollup作为打包工具,号称下一代的前端构建工具。vite是一种新型的前端构建工具,能够显著的提升前端开发者的体验。它主要有俩部分组成:一个</div> </li> <li><a href="/article/1943972599818153984.htm" title="本地包解决npm error code E404" target="_blank">本地包解决npm error code E404</a> <span class="text-muted">雅痞yuppie</span> <a class="tag" taget="_blank" href="/search/npm/1.htm">npm</a><a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF/1.htm">前端</a><a class="tag" taget="_blank" href="/search/node.js/1.htm">node.js</a> <div>这个错误提示表明npm找不到名为create-vue-admin-cli的包。这是因为你开发的CLI工具还没有发布到npm官方注册表。要解决这个问题,有两种方法:方法一:使用本地开发模式测试1.确保你的CLI已正确链接到全局在你的vue-admin-cli项目根目录下执行:npmlink这会在全局环境中创建一个符号链接,指向你本地的CLI项目。2.使用本地链接的CLI创建项目直接使用命令:vue-</div> </li> <li><a href="/article/1943971211121848320.htm" title="前端 NPM 包的依赖可视化分析工具推荐" target="_blank">前端 NPM 包的依赖可视化分析工具推荐</a> <span class="text-muted">前端视界</span> <a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF%E8%89%BA%E5%8C%A0%E9%A6%86/1.htm">前端艺匠馆</a><a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF/1.htm">前端</a><a class="tag" taget="_blank" href="/search/npm/1.htm">npm</a><a class="tag" taget="_blank" href="/search/arcgis/1.htm">arcgis</a><a class="tag" taget="_blank" href="/search/ai/1.htm">ai</a> <div>前端NPM包的依赖可视化分析工具推荐关键词:NPM、依赖管理、可视化分析、前端工程、包管理、依赖冲突、性能优化摘要:本文将深入探讨前端开发中NPM包依赖可视化分析的重要性,介绍5款主流工具的使用方法和特点,并通过实际案例展示如何利用这些工具优化项目依赖结构、解决版本冲突问题以及提升构建性能。文章将帮助开发者更好地理解和掌控项目依赖关系,提高开发效率和项目可维护性。背景介绍目的和范围本文旨在为前端开</div> </li> <li><a href="/article/1943969826485628928.htm" title="cesium添加原生MVT矢量瓦片方案" target="_blank">cesium添加原生MVT矢量瓦片方案</a> <span class="text-muted">zhu_zhu_xia</span> <a class="tag" taget="_blank" href="/search/cesium/1.htm">cesium</a><a class="tag" taget="_blank" href="/search/vue/1.htm">vue</a><a class="tag" taget="_blank" href="/search/arcgis/1.htm">arcgis</a><a class="tag" taget="_blank" href="/search/cesium/1.htm">cesium</a><a class="tag" taget="_blank" href="/search/webgl/1.htm">webgl</a><a class="tag" taget="_blank" href="/search/javascript/1.htm">javascript</a> <div>项目中需要基于cesium接入mvt格式的服务并支持属性拾取查询,通过一系列预研测试,最后选择cesium-mvt-imagery-provider开源插件完成,关键源码信息如下:npmicesiumcesium-mvt-imagery-provider//安装依赖包//加载图层importCesiumMVTImageryProviderfrom"cesium-mvt-imagery-provid</div> </li> <li><a href="/article/1943969321717919744.htm" title="日历插件-FullCalendar的详细使用" target="_blank">日历插件-FullCalendar的详细使用</a> <span class="text-muted">老马聊技术</span> <a class="tag" taget="_blank" href="/search/JavaScript/1.htm">JavaScript</a><a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF/1.htm">前端</a><a class="tag" taget="_blank" href="/search/javascript/1.htm">javascript</a> <div>一、介绍FullCalendar是一个功能强大、高度可定制的JavaScript日历组件,用于在网页中显示和管理日历事件。它支持多种视图(月、周、日等),可以轻松集成各种框架,并提供丰富的事件处理功能。二、实操案例具体代码如下:FullCalendar日期选择body{font-family:Arial,sans-serif;margin:20px;}#calendar{max-width:900</div> </li> <li><a href="/article/1943963776244051968.htm" title="入门html这篇文章就够了" target="_blank">入门html这篇文章就够了</a> <span class="text-muted">ξ流ぁ星ぷ132</span> <a class="tag" taget="_blank" href="/search/html/1.htm">html</a><a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF/1.htm">前端</a> <div>HTML笔记文章目录HTML笔记html介绍什么是htmlhtml的作用HTML标签介绍常用标签标签and标签and标签u标签del删除线br标签用于换行pre标签,预处理标签span标签div标签sub标签andsup标签hr标签h1,h2...h6标签:HTML5中的语义标签:特殊字符img标签a标签第一种用法:超链接第二种用法:锚点video标签表格标签:form标签input标签selec</div> </li> <li><a href="/article/1943963649831923712.htm" title="玩转Docker | 使用Docker部署gopeed下载工具" target="_blank">玩转Docker | 使用Docker部署gopeed下载工具</a> <span class="text-muted">心随_风动</span> <a class="tag" taget="_blank" href="/search/%E7%8E%A9%E8%BD%ACDocker/1.htm">玩转Docker</a><a class="tag" taget="_blank" href="/search/docker/1.htm">docker</a><a class="tag" taget="_blank" href="/search/%E5%AE%B9%E5%99%A8/1.htm">容器</a><a class="tag" taget="_blank" href="/search/%E8%BF%90%E7%BB%B4/1.htm">运维</a> <div>玩转Docker|使用Docker部署gopeed下载工具前言一、gopeed介绍Gopeed简介主要特点二、系统要求环境要求环境检查Docker版本检查检查操作系统版本三、部署gopeed服务下载镜像创建容器检查容器状态检查服务端口安全设置四、访问gopeed应用五、测试与下载六、总结前言在当今信息爆炸的时代,高效地获取和管理网络资源变得尤为重要。无论是下载大型文件还是进行日常的数据传输,一个稳</div> </li> <li><a href="/article/1943963271782526976.htm" title="android判断深色模式的方法" target="_blank">android判断深色模式的方法</a> <span class="text-muted">东东旭huster</span> <a class="tag" taget="_blank" href="/search/android/1.htm">android</a><a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a> <div>android10以后的版本才完全支持深色模式,测试下面两种方法判断系统是否深色模式都是有效的。publicstaticbooleanisDarkMode1(){if(Build.VERSION.SDK_INT<Build.VERSION_CODES.Q){returnfalse;}Contextcontext=LauncherApplicationAgent.getInstance().getA</div> </li> <li><a href="/article/1943961125532004352.htm" title="数字孪生技术为UI前端注入新活力:实现产品设计的沉浸式体验" target="_blank">数字孪生技术为UI前端注入新活力:实现产品设计的沉浸式体验</a> <span class="text-muted">ui设计前端开发老司机</span> <a class="tag" taget="_blank" href="/search/ui/1.htm">ui</a> <div>hello宝子们...我们是艾斯视觉擅长ui设计、前端开发、数字孪生、大数据、三维建模、三维动画10年+经验!希望我的分享能帮助到您!如需帮助可以评论关注私信我们一起探讨!致敬感谢感恩!一、引言:从“平面交互”到“沉浸体验”的UI革命当用户在电商APP中翻看3D家具模型却无法感知其与自家客厅的匹配度,当设计师在2D屏幕上绘制汽车内饰却难以预判实际乘坐体验——传统UI设计的“平面化、静态化、割裂感”</div> </li> <li><a href="/article/1943954447797383168.htm" title="javascript高级程序设计第3版——第12章 DOM2与DOM3" target="_blank">javascript高级程序设计第3版——第12章 DOM2与DOM3</a> <span class="text-muted">weixin_30687587</span> <a class="tag" taget="_blank" href="/search/javascript/1.htm">javascript</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84%E4%B8%8E%E7%AE%97%E6%B3%95/1.htm">数据结构与算法</a><a class="tag" taget="_blank" href="/search/ViewUI/1.htm">ViewUI</a> <div>12章——DOM2与DOM3为了增强D0M1,DOM级规范定义了一些模块。DOM2核心:为不同的DOM类型引入了一些与XML命名空间有关的方法,还定义了以编程方式创建Document实例的方法;DOM2级样式:针对操作元素的样式而开发;其特性总结:1.每个元素都有一个关联的style对象,可用来确定和修改行内样式;2.要确定某个元素的计算样式,可使用getComgetComputedStyle()</div> </li> <li><a href="/article/1943950163496202240.htm" title="JavaScript 基础09:Web APIs——日期对象、DOM节点" target="_blank">JavaScript 基础09:Web APIs——日期对象、DOM节点</a> <span class="text-muted">梦想当全栈</span> <a class="tag" taget="_blank" href="/search/JavaScript/1.htm">JavaScript</a><a class="tag" taget="_blank" href="/search/javascript/1.htm">javascript</a><a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF/1.htm">前端</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a> <div>JavaScript基础09:WebAPIs——日期对象、DOM节点进一步学习DOM相关知识,实现可交互的网页特效能够插入、删除和替换元素节点。能够依据元素节点关系查找节点。一、日期对象掌握Date日期对象的使用,动态获取当前计算机的时间。ECMAScript中内置了获取系统时间的对象Date,使用Date时与之前学习的内置对象console和Math不同,它需要借助new关键字才能使用。1.实例</div> </li> <li><a href="/article/1943948145373278208.htm" title="Topview Avatar 2深度实测:AI数字人带货的新高度,还是又一个营销噱头?" target="_blank">Topview Avatar 2深度实测:AI数字人带货的新高度,还是又一个营销噱头?</a> <span class="text-muted">神码小Z</span> <a class="tag" taget="_blank" href="/search/AI%E5%B7%A5%E5%85%B7/1.htm">AI工具</a><a class="tag" taget="_blank" href="/search/%E4%BA%BA%E5%B7%A5%E6%99%BA%E8%83%BD/1.htm">人工智能</a> <div>在AI数字人赛道越来越卷的今天,各家产品都在宣传自己的"独门秘技"。最近,TopviewAI推出的Avatar2引起了我的注意——号称突破了产品尺寸限制,实现了"万物皆可带"。作为一个经常需要制作营销视频的内容创作者,我决定亲自上手测试一番,看看这款工具是否真的像宣传的那样强大。TopviewAvatar2是什么?革命性升级还是渐进式改良?TopviewAvatar2是TopviewAI推出的第二</div> </li> <li><a href="/article/1943946255763828736.htm" title="《Java前端开发全栈指南:从Servlet到现代框架实战》" target="_blank">《Java前端开发全栈指南:从Servlet到现代框架实战》</a> <span class="text-muted"></span> <div>前言在当今Web开发领域,Java依然是后端开发的主力语言,而随着前后端分离架构的普及,Java开发者也需要掌握前端技术栈。本文将全面介绍JavaWeb前端开发的核心技术,包括传统Servlet/JSP体系、现代前端框架集成方案,以及全栈开发的最佳实践。通过本文,您将了解如何构建现代化的JavaWeb应用前端界面。一、JavaWeb前端技术演进1.1传统技术栈Servlet:JavaWeb基础,处</div> </li> <li><a href="/article/1943940584297263104.htm" title="【华为机试】HJ61 放苹果" target="_blank">【华为机试】HJ61 放苹果</a> <span class="text-muted">不爱熬夜的Coder</span> <a class="tag" taget="_blank" href="/search/%E7%AE%97%E6%B3%95/1.htm">算法</a><a class="tag" taget="_blank" href="/search/%E5%8D%8E%E4%B8%BA%E6%9C%BA%E8%AF%95/1.htm">华为机试</a><a class="tag" taget="_blank" href="/search/golang/1.htm">golang</a><a class="tag" taget="_blank" href="/search/%E5%8D%8E%E4%B8%BA/1.htm">华为</a><a class="tag" taget="_blank" href="/search/golang/1.htm">golang</a><a class="tag" taget="_blank" href="/search/%E7%AE%97%E6%B3%95/1.htm">算法</a><a class="tag" taget="_blank" href="/search/%E9%9D%A2%E8%AF%95/1.htm">面试</a> <div>文章目录HJ61放苹果描述输入描述输出描述示例1示例2解题思路算法分析问题本质分析状态定义与转移递推关系详解动态规划表构建算法流程图示例推导过程代码实现思路时间复杂度分析关键优化点边界情况处理递归解法对比实际应用场景测试用例分析算法特点数学原理完整题解代码HJ61放苹果描述我们需要将m个相同的苹果放入n个相同的盘子中,允许有的盘子空着不放。求解有多少种不同的分法。输入描述输入两个整数m,n(0B[</div> </li> <li><a href="/article/1943932016164663296.htm" title="Vue3组件库实战: 打造高复用UI系统" target="_blank">Vue3组件库实战: 打造高复用UI系统</a> <span class="text-muted">武昌库里写JAVA</span> <a class="tag" taget="_blank" href="/search/%E9%9D%A2%E8%AF%95%E9%A2%98%E6%B1%87%E6%80%BB%E4%B8%8E%E8%A7%A3%E6%9E%90/1.htm">面试题汇总与解析</a><a class="tag" taget="_blank" href="/search/%E8%AF%BE%E7%A8%8B%E8%AE%BE%E8%AE%A1/1.htm">课程设计</a><a class="tag" taget="_blank" href="/search/spring/1.htm">spring</a><a class="tag" taget="_blank" href="/search/boot/1.htm">boot</a><a class="tag" taget="_blank" href="/search/vue.js/1.htm">vue.js</a><a class="tag" taget="_blank" href="/search/layui/1.htm">layui</a><a class="tag" taget="_blank" href="/search/%E6%AF%95%E4%B8%9A%E8%AE%BE%E8%AE%A1/1.htm">毕业设计</a> <div>Vue3组件库实战:打造高复用UI系统介绍什么是Vue3组件库在前端开发中,UI组件库是非常重要的一部分。Vue3组件库是基于Vue.js3.x版本开发的一套可用于构建Web应用的UI组件集合,可以帮助开发者快速搭建页面并保证页面的一致性和美观性。目标关键词:Vue3组件库设计与构建设计原则组件库的设计需要遵循一定的原则,比如易用性、可维护性、扩展性等。在设计阶段需要考虑到不同场景的使用,并且保证</div> </li> <li><a href="/article/1943926592141062144.htm" title="Flutter——数据库Drift开发详细教程之迁移(九)" target="_blank">Flutter——数据库Drift开发详细教程之迁移(九)</a> <span class="text-muted">怀君</span> <a class="tag" taget="_blank" href="/search/flutter/1.htm">flutter</a><a class="tag" taget="_blank" href="/search/flutter/1.htm">flutter</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E5%BA%93/1.htm">数据库</a> <div>迁移入门引导式迁移配置用法例子切换到make-migrations开发过程中手动迁移迁移后回调导出模式导出架构下一步是什么?调试导出架构的问题修复这个问题架构迁移助手自定义分步迁移转向逐步迁移手动生成测试迁移编写测试验证数据完整性在运行时验证数据库模式迁移器API一般提示迁移视图、触发器和索引复杂的迁移更改列的类型更改列约束删除列重命名列合并列添加新列入门Drift通过严格的架构确保查询类型安全。</div> </li> <li><a href="/article/1943920035919622144.htm" title="2025年渗透测试面试题总结-2025年HW(护网面试) 43(题目+回答)" target="_blank">2025年渗透测试面试题总结-2025年HW(护网面试) 43(题目+回答)</a> <span class="text-muted">独行soc</span> <a class="tag" taget="_blank" href="/search/2025%E5%B9%B4%E6%8A%A4%E7%BD%91/1.htm">2025年护网</a><a class="tag" taget="_blank" href="/search/%E9%9D%A2%E8%AF%95/1.htm">面试</a><a class="tag" taget="_blank" href="/search/%E8%81%8C%E5%9C%BA%E5%92%8C%E5%8F%91%E5%B1%95/1.htm">职场和发展</a><a class="tag" taget="_blank" href="/search/linux/1.htm">linux</a><a class="tag" taget="_blank" href="/search/%E7%A7%91%E6%8A%80/1.htm">科技</a><a class="tag" taget="_blank" href="/search/%E6%B8%97%E9%80%8F%E6%B5%8B%E8%AF%95/1.htm">渗透测试</a><a class="tag" taget="_blank" href="/search/%E5%AE%89%E5%85%A8/1.htm">安全</a><a class="tag" taget="_blank" href="/search/%E6%8A%A4%E7%BD%91/1.htm">护网</a> <div>安全领域各种资源,学习文档,以及工具分享、前沿信息分享、POC、EXP分享。不定期分享各种好玩的项目及好用的工具,欢迎关注。目录2025年HW(护网面试)431.自我介绍与职业规划2.Webshell源码级检测方案3.2025年新型Web漏洞TOP54.渗透中的高价值攻击点5.智能Fuzz平台架构设计6.堆栈溢出攻防演进7.插桩技术实战应用8.二进制安全能力矩阵9.C语言内存管理精要10.Pyth</div> </li> <li><a href="/article/1943919909612351488.htm" title="Vue.js 过渡 & 动画" target="_blank">Vue.js 过渡 & 动画</a> <span class="text-muted">lsx202406</span> <a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a> <div>Vue.js过渡&动画引言在Web开发中,过渡与动画是提升用户体验的关键元素。Vue.js作为一款流行的前端框架,提供了强大的过渡与动画功能,使得开发者能够轻松实现丰富的交互效果。本文将深入探讨Vue.js中的过渡与动画,包括其原理、应用场景以及实现方法。一、Vue.js过渡原理Vue.js过渡是利用CSS3的transition属性实现的。当Vue.js侦测到数据变化时,会自动触发过渡效果。过渡</div> </li> <li><a href="/article/1943919026744913920.htm" title="JavaScript之DOM操作与事件处理详解" target="_blank">JavaScript之DOM操作与事件处理详解</a> <span class="text-muted">AA-代码批发V哥</span> <a class="tag" taget="_blank" href="/search/JavaScript/1.htm">JavaScript</a><a class="tag" taget="_blank" href="/search/javascript/1.htm">javascript</a> <div>JavaScript之DOM操作与事件处理详解一、DOM基础:理解文档对象模型二、DOM元素的获取与访问2.1基础获取方法2.2集合的区别与注意事项三、DOM元素的创建与修改3.1创建与插入元素3.2修改元素属性与样式3.2.1属性操作3.2.2样式操作3.3元素内容的修改四、DOM元素的删除与替换4.1删除元素4.2替换元素五、事件处理:实现页面交互5.1事件绑定的三种方式5.1.1HTML属性</div> </li> <li><a href="/article/1943917893620133888.htm" title="V少JS基础班之第五弹" target="_blank">V少JS基础班之第五弹</a> <span class="text-muted">V少在逆向</span> <a class="tag" taget="_blank" href="/search/JS%E5%9F%BA%E7%A1%80%E7%8F%AD/1.htm">JS基础班</a><a class="tag" taget="_blank" href="/search/javascript/1.htm">javascript</a><a class="tag" taget="_blank" href="/search/%E5%BC%80%E5%8F%91%E8%AF%AD%E8%A8%80/1.htm">开发语言</a><a class="tag" taget="_blank" href="/search/ecmascript/1.htm">ecmascript</a> <div>文章目录一、前言二、本节涉及知识点三、重点内容1-函数的定义2-函数的构成1.函数参数详解1)参数个数不固定2)默认参数3)arguments对象(类数组)4)剩余参数(Rest参数)5)函数参数是按值传递的6)解构参数传递7)参数校验技巧(JavaScript没有类型限制,需要手动校验)2.函数返回值详解3-函数的分类1-函数声明式:2-函数表达式:3-箭头函数:4-构造函数:5-IIFE:6-</div> </li> <li><a href="/article/1943917011268595712.htm" title="Javaweb学习之Vue模板语法(三)" target="_blank">Javaweb学习之Vue模板语法(三)</a> <span class="text-muted">不要数手指啦</span> <a class="tag" taget="_blank" href="/search/vue.js/1.htm">vue.js</a><a class="tag" taget="_blank" href="/search/%E5%AD%A6%E4%B9%A0/1.htm">学习</a><a class="tag" taget="_blank" href="/search/%E5%89%8D%E7%AB%AF/1.htm">前端</a> <div>目录学习资料前情回顾本期介绍(vue模板语法)文本插值Vue的Attribute绑定使用JavaScript表达式综合实例代码:学习资料Vue.js-渐进式JavaScript框架|Vue.js(vuejs.org)前情回顾项目的创建大家可以看这篇文章Vue学习之项目的创建-CSDN博客本期介绍(vue模板语法)首先,找到我们编写代码的地方找到自己项目的src文件夹,打开之后点击component</div> </li> <li><a href="/article/118.htm" title="异常的核心类Throwable" target="_blank">异常的核心类Throwable</a> <span class="text-muted">无量</span> <a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E6%BA%90%E7%A0%81/1.htm">源码</a><a class="tag" taget="_blank" href="/search/%E5%BC%82%E5%B8%B8%E5%A4%84%E7%90%86/1.htm">异常处理</a><a class="tag" taget="_blank" href="/search/exception/1.htm">exception</a> <div>java异常的核心是Throwable,其他的如Error和Exception都是继承的这个类 里面有个核心参数是detailMessage,记录异常信息,getMessage核心方法,获取这个参数的值,我们可以自己定义自己的异常类,去继承这个Exception就可以了,方法基本上,用父类的构造方法就OK,所以这么看异常是不是很easy package com.natsu; </div> </li> <li><a href="/article/245.htm" title="mongoDB 游标(cursor) 实现分页 迭代" target="_blank">mongoDB 游标(cursor) 实现分页 迭代</a> <span class="text-muted">开窍的石头</span> <a class="tag" taget="_blank" href="/search/mongodb/1.htm">mongodb</a> <div>上篇中我们讲了mongoDB 中的查询函数,现在我们讲mongo中如何做分页查询      如何声明一个游标        var mycursor = db.user.find({_id:{$lte:5}});       迭代显示游标数</div> </li> <li><a href="/article/372.htm" title="MySQL数据库INNODB 表损坏修复处理过程" target="_blank">MySQL数据库INNODB 表损坏修复处理过程</a> <span class="text-muted">0624chenhong</span> <a class="tag" taget="_blank" href="/search/tomcat/1.htm">tomcat</a><a class="tag" taget="_blank" href="/search/mysql/1.htm">mysql</a> <div>最近mysql数据库经常死掉,用命令net stop mysql命令也无法停掉,关闭Tomcat的时候,出现Waiting for N instance(s) to be deallocated 信息。查了下,大概就是程序没有对数据库连接释放,导致Connection泄露了。因为用的是开元集成的平台,内部程序也不可能一下子给改掉的,就验证一下咯。启动Tomcat,用户登录系统,用netstat -</div> </li> <li><a href="/article/499.htm" title="剖析如何与设计人员沟通" target="_blank">剖析如何与设计人员沟通</a> <span class="text-muted">不懂事的小屁孩</span> <a class="tag" taget="_blank" href="/search/%E5%B7%A5%E4%BD%9C/1.htm">工作</a> <div>最近做图烦死了,不停的改图,改图……。烦,倒不是因为改,而是反反复复的改,人都会死。很多需求人员不知该如何与设计人员沟通,不明白如何使设计人员知道他所要的效果,结果只能是沟通变成了扯淡,改图变成了应付。 那应该如何与设计人员沟通呢? 我认为设计人员与需求人员先天就存在语言障碍。对一个合格的设计人员来说,整天玩的都是点、线、面、配色,哪种构图看起来协调;哪种配色看起来合理心里跟明镜似的,</div> </li> <li><a href="/article/626.htm" title="qq空间刷评论工具" target="_blank">qq空间刷评论工具</a> <span class="text-muted">换个号韩国红果果</span> <a class="tag" taget="_blank" href="/search/JavaScript/1.htm">JavaScript</a> <div> var a=document.getElementsByClassName('textinput'); var b=[]; for(var m=0;m<a.length;m++){ if(a[m].getAttribute('placeholder')!=null) b.push(a[m]) } var l</div> </li> <li><a href="/article/753.htm" title="S2SH整合之session" target="_blank">S2SH整合之session</a> <span class="text-muted">灵静志远</span> <a class="tag" taget="_blank" href="/search/spring/1.htm">spring</a><a class="tag" taget="_blank" href="/search/AOP/1.htm">AOP</a><a class="tag" taget="_blank" href="/search/struts/1.htm">struts</a><a class="tag" taget="_blank" href="/search/session/1.htm">session</a> <div>错误信息: Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'cartService': Scope 'session' is not active for the current thread; consider defining a scoped</div> </li> <li><a href="/article/880.htm" title="xmp标签" target="_blank">xmp标签</a> <span class="text-muted">a-john</span> <a class="tag" taget="_blank" href="/search/%E6%A0%87%E7%AD%BE/1.htm">标签</a> <div>今天在处理数据的显示上遇到一个问题: var html = '<li><div class="pl-nr"><span class="user-name">' + user + '</span>' + text + '</div></li>'; ulComme</div> </li> <li><a href="/article/1007.htm" title="Ajax的常用技巧(2)---实现Web页面中的级联菜单" target="_blank">Ajax的常用技巧(2)---实现Web页面中的级联菜单</a> <span class="text-muted">aijuans</span> <a class="tag" taget="_blank" href="/search/Ajax/1.htm">Ajax</a> <div>在网络上显示数据,往往只显示数据中的一部分信息,如文章标题,产品名称等。如果浏览器要查看所有信息,只需点击相关链接即可。在web技术中,可以采用级联菜单完成上述操作。根据用户的选择,动态展开,并显示出对应选项子菜单的内容。 在传统的web实现方式中,一般是在页面初始化时动态获取到服务端数据库中对应的所有子菜单中的信息,放置到页面中对应的位置,然后再结合CSS层叠样式表动态控制对应子菜单的显示或者隐</div> </li> <li><a href="/article/1134.htm" title="天-安-门,好高" target="_blank">天-安-门,好高</a> <span class="text-muted">atongyeye</span> <a class="tag" taget="_blank" href="/search/%E6%83%85%E6%84%9F/1.htm">情感</a> <div>    我是85后,北漂一族,之前房租1100,因为租房合同到期,再续,房租就要涨150。最近网上新闻,地铁也要涨价。算了一下,涨价之后,每次坐地铁由原来2块变成6块。仅坐地铁费用,一个月就要涨200。内心苦痛。     晚上躺在床上一个人想了很久,很久。        我生在农</div> </li> <li><a href="/article/1261.htm" title="android 动画" target="_blank">android 动画</a> <span class="text-muted">百合不是茶</span> <a class="tag" taget="_blank" href="/search/android/1.htm">android</a><a class="tag" taget="_blank" href="/search/%E9%80%8F%E6%98%8E%E5%BA%A6/1.htm">透明度</a><a class="tag" taget="_blank" href="/search/%E5%B9%B3%E7%A7%BB/1.htm">平移</a><a class="tag" taget="_blank" href="/search/%E7%BC%A9%E6%94%BE/1.htm">缩放</a><a class="tag" taget="_blank" href="/search/%E6%97%8B%E8%BD%AC/1.htm">旋转</a> <div>android的动画有两种  tween动画和Frame动画   tween动画;,透明度,缩放,旋转,平移效果   Animation   动画 AlphaAnimation 渐变透明度 RotateAnimation 画面旋转 ScaleAnimation 渐变尺寸缩放 TranslateAnimation 位置移动 Animation</div> </li> <li><a href="/article/1388.htm" title="查看本机网络信息的cmd脚本" target="_blank">查看本机网络信息的cmd脚本</a> <span class="text-muted">bijian1013</span> <a class="tag" taget="_blank" href="/search/cmd/1.htm">cmd</a> <div>@echo 您的用户名是:%USERDOMAIN%\%username%>"%userprofile%\网络参数.txt" @echo 您的机器名是:%COMPUTERNAME%>>"%userprofile%\网络参数.txt" @echo ___________________>>"%userprofile%\</div> </li> <li><a href="/article/1515.htm" title="plsql 清除登录过的用户" target="_blank">plsql 清除登录过的用户</a> <span class="text-muted">征客丶</span> <a class="tag" taget="_blank" href="/search/plsql/1.htm">plsql</a> <div>tools---preferences----logon history---history  把你想要删除的删除 -------------------------------------------------------------------- 若有其他凝问或文中有错误,请及时向我指出, 我好及时改正,同时也让我们一起进步。 email : binary_spac</div> </li> <li><a href="/article/1642.htm" title="【Pig一】Pig入门" target="_blank">【Pig一】Pig入门</a> <span class="text-muted">bit1129</span> <a class="tag" taget="_blank" href="/search/pig/1.htm">pig</a> <div>Pig安装 1.下载pig   wget http://mirror.bit.edu.cn/apache/pig/pig-0.14.0/pig-0.14.0.tar.gz   2. 解压配置环境变量      如果Pig使用Map/Reduce模式,那么需要在环境变量中,配置HADOOP_HOME环境变量   expor</div> </li> <li><a href="/article/1769.htm" title="Java 线程同步几种方式" target="_blank">Java 线程同步几种方式</a> <span class="text-muted">BlueSkator</span> <a class="tag" taget="_blank" href="/search/volatile/1.htm">volatile</a><a class="tag" taget="_blank" href="/search/synchronized/1.htm">synchronized</a><a class="tag" taget="_blank" href="/search/ThredLocal/1.htm">ThredLocal</a><a class="tag" taget="_blank" href="/search/ReenTranLock/1.htm">ReenTranLock</a><a class="tag" taget="_blank" href="/search/Concurrent/1.htm">Concurrent</a> <div>为何要使用同步?      java允许多线程并发控制,当多个线程同时操作一个可共享的资源变量时(如数据的增删改查),      将会导致数据不准确,相互之间产生冲突,因此加入同步锁以避免在该线程没有完成操作之前,被其他线程的调用,      从而保证了该变量的唯一性和准确性。 1.同步方法&</div> </li> <li><a href="/article/1896.htm" title="StringUtils判断字符串是否为空的方法(转帖)" target="_blank">StringUtils判断字符串是否为空的方法(转帖)</a> <span class="text-muted">BreakingBad</span> <a class="tag" taget="_blank" href="/search/null/1.htm">null</a><a class="tag" taget="_blank" href="/search/StringUtils/1.htm">StringUtils</a><a class="tag" taget="_blank" href="/search/%E2%80%9C%E2%80%9D/1.htm">“”</a> <div>转帖地址:http://www.cnblogs.com/shangxiaofei/p/4313111.html   public static boolean isEmpty(String str)     判断某字符串是否为空,为空的标准是 str== null  或 str.length()== 0  </div> </li> <li><a href="/article/2023.htm" title="编程之美-分层遍历二叉树" target="_blank">编程之美-分层遍历二叉树</a> <span class="text-muted">bylijinnan</span> <a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84/1.htm">数据结构</a><a class="tag" taget="_blank" href="/search/%E7%AE%97%E6%B3%95/1.htm">算法</a><a class="tag" taget="_blank" href="/search/%E7%BC%96%E7%A8%8B%E4%B9%8B%E7%BE%8E/1.htm">编程之美</a> <div> import java.util.ArrayList; import java.util.LinkedList; import java.util.List; public class LevelTraverseBinaryTree { /** * 编程之美 分层遍历二叉树 * 之前已经用队列实现过二叉树的层次遍历,但这次要求输出换行,因此要</div> </li> <li><a href="/article/2150.htm" title="jquery取值和ajax提交复习记录" target="_blank">jquery取值和ajax提交复习记录</a> <span class="text-muted">chengxuyuancsdn</span> <a class="tag" taget="_blank" href="/search/jquery%E5%8F%96%E5%80%BC/1.htm">jquery取值</a><a class="tag" taget="_blank" href="/search/ajax%E6%8F%90%E4%BA%A4/1.htm">ajax提交</a> <div> // 取值 // alert($("input[name='username']").val()); // alert($("input[name='password']").val()); // alert($("input[name='sex']:checked").val()); // alert($("</div> </li> <li><a href="/article/2277.htm" title="推荐国产工作流引擎嵌入式公式语法解析器-IK Expression" target="_blank">推荐国产工作流引擎嵌入式公式语法解析器-IK Expression</a> <span class="text-muted">comsci</span> <a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E5%BA%94%E7%94%A8%E6%9C%8D%E5%8A%A1%E5%99%A8/1.htm">应用服务器</a><a class="tag" taget="_blank" href="/search/%E5%B7%A5%E4%BD%9C/1.htm">工作</a><a class="tag" taget="_blank" href="/search/Excel/1.htm">Excel</a><a class="tag" taget="_blank" href="/search/%E5%B5%8C%E5%85%A5%E5%BC%8F/1.htm">嵌入式</a> <div>这个开源软件包是国内的一位高手自行研制开发的,正如他所说的一样,我觉得它可以使一个工作流引擎上一个台阶。。。。。。欢迎大家使用,并提出意见和建议。。。 ----------转帖--------------------------------------------------- IK Expression是一个开源的(OpenSource),可扩展的(Extensible),基于java语言</div> </li> <li><a href="/article/2404.htm" title="关于系统中使用多个PropertyPlaceholderConfigurer的配置及PropertyOverrideConfigurer" target="_blank">关于系统中使用多个PropertyPlaceholderConfigurer的配置及PropertyOverrideConfigurer</a> <span class="text-muted">daizj</span> <a class="tag" taget="_blank" href="/search/spring/1.htm">spring</a> <div>1、PropertyPlaceholderConfigurer Spring中PropertyPlaceholderConfigurer这个类,它是用来解析Java Properties属性文件值,并提供在spring配置期间替换使用属性值。接下来让我们逐渐的深入其配置。 基本的使用方法是:(1) <bean id="propertyConfigurerForWZ&q</div> </li> <li><a href="/article/2531.htm" title="二叉树:二叉搜索树" target="_blank">二叉树:二叉搜索树</a> <span class="text-muted">dieslrae</span> <a class="tag" taget="_blank" href="/search/%E4%BA%8C%E5%8F%89%E6%A0%91/1.htm">二叉树</a> <div>    所谓二叉树,就是一个节点最多只能有两个子节点,而二叉搜索树就是一个经典并简单的二叉树.规则是一个节点的左子节点一定比自己小,右子节点一定大于等于自己(当然也可以反过来).在树基本平衡的时候插入,搜索和删除速度都很快,时间复杂度为O(logN).但是,如果插入的是有序的数据,那效率就会变成O(N),在这个时候,树其实变成了一个链表. tree代码: </div> </li> <li><a href="/article/2658.htm" title="C语言字符串函数大全" target="_blank">C语言字符串函数大全</a> <span class="text-muted">dcj3sjt126com</span> <a class="tag" taget="_blank" href="/search/c/1.htm">c</a><a class="tag" taget="_blank" href="/search/function/1.htm">function</a> <div>C语言字符串函数大全     函数名: stpcpy 功 能: 拷贝一个字符串到另一个 用 法: char *stpcpy(char *destin, char *source); 程序例:   #include <stdio.h> #include <string.h>   int main</div> </li> <li><a href="/article/2785.htm" title="友盟统计页面技巧" target="_blank">友盟统计页面技巧</a> <span class="text-muted">dcj3sjt126com</span> <a class="tag" taget="_blank" href="/search/%E6%8A%80%E5%B7%A7/1.htm">技巧</a> <div>在基类调用就可以了, 基类ViewController示例代码 -(void)viewWillAppear:(BOOL)animated { [super viewWillAppear:animated]; [MobClick beginLogPageView:[NSString stringWithFormat:@"%@",self.class]]; </div> </li> <li><a href="/article/2912.htm" title="window下在同一台机器上安装多个版本jdk,修改环境变量不生效问题处理办法" target="_blank">window下在同一台机器上安装多个版本jdk,修改环境变量不生效问题处理办法</a> <span class="text-muted">flyvszhb</span> <a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/jdk/1.htm">jdk</a> <div>window下在同一台机器上安装多个版本jdk,修改环境变量不生效问题处理办法 本机已经安装了jdk1.7,而比较早期的项目需要依赖jdk1.6,于是同时在本机安装了jdk1.6和jdk1.7. 安装jdk1.6前,执行java -version得到 C:\Users\liuxiang2>java -version java version "1.7.0_21&quo</div> </li> <li><a href="/article/3039.htm" title="Java在创建子类对象的同时会不会创建父类对象" target="_blank">Java在创建子类对象的同时会不会创建父类对象</a> <span class="text-muted">happyqing</span> <a class="tag" taget="_blank" href="/search/java/1.htm">java</a><a class="tag" taget="_blank" href="/search/%E5%88%9B%E5%BB%BA/1.htm">创建</a><a class="tag" taget="_blank" href="/search/%E5%AD%90%E7%B1%BB%E5%AF%B9%E8%B1%A1/1.htm">子类对象</a><a class="tag" taget="_blank" href="/search/%E7%88%B6%E7%B1%BB%E5%AF%B9%E8%B1%A1/1.htm">父类对象</a> <div>  1.在thingking in java 的第四版第六章中明确的说了,子类对象中封装了父类对象,   2."When you create an object of the derived class, it contains within it a subobject of the base class. This subobject is the sam</div> </li> <li><a href="/article/3166.htm" title="跟我学spring3 目录贴及电子书下载" target="_blank">跟我学spring3 目录贴及电子书下载</a> <span class="text-muted">jinnianshilongnian</span> <a class="tag" taget="_blank" href="/search/spring/1.htm">spring</a> <div>    一、《跟我学spring3》电子书下载地址: 《跟我学spring3》  (1-7 和 8-13) http://jinnianshilongnian.iteye.com/blog/pdf     跟我学spring3系列 word原版 下载     二、 源代码下载 最新依</div> </li> <li><a href="/article/3420.htm" title="第12章 Ajax(上)" target="_blank">第12章 Ajax(上)</a> <span class="text-muted">onestopweb</span> <a class="tag" taget="_blank" href="/search/Ajax/1.htm">Ajax</a> <div>index.html <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/</div> </li> <li><a href="/article/3547.htm" title="BI and EIM 4.0 at a glance" target="_blank">BI and EIM 4.0 at a glance</a> <span class="text-muted">blueoxygen</span> <a class="tag" taget="_blank" href="/search/BO/1.htm">BO</a> <div>http://www.sap.com/corporate-en/press.epx?PressID=14787   有机会研究下EIM家族的两个新产品~~~~   New features of the 4.0 releases of BI and EIM solutions include: Real-time in-memory computing – </div> </li> <li><a href="/article/3674.htm" title="Java线程中yield与join方法的区别" target="_blank">Java线程中yield与join方法的区别</a> <span class="text-muted">tomcat_oracle</span> <a class="tag" taget="_blank" href="/search/java/1.htm">java</a> <div>长期以来,多线程问题颇为受到面试官的青睐。虽然我个人认为我们当中很少有人能真正获得机会开发复杂的多线程应用(在过去的七年中,我得到了一个机会),但是理解多线程对增加你的信心很有用。之前,我讨论了一个wait()和sleep()方法区别的问题,这一次,我将会讨论join()和yield()方法的区别。坦白的说,实际上我并没有用过其中任何一个方法,所以,如果你感觉有不恰当的地方,请提出讨论。 &nb</div> </li> <li><a href="/article/3801.htm" title="android Manifest.xml选项" target="_blank">android Manifest.xml选项</a> <span class="text-muted">阿尔萨斯</span> <a class="tag" taget="_blank" href="/search/Manifest/1.htm">Manifest</a> <div>结构 继承关系 public final class Manifest extends Objectjava.lang.Objectandroid.Manifest 内部类 class Manifest.permission权限 class Manifest.permission_group权限组 构造函数 public Manifest () 详细 androi</div> </li> <li><a href="/article/3928.htm" title="Oracle实现类split函数的方" target="_blank">Oracle实现类split函数的方</a> <span class="text-muted">zhaoshijie</span> <a class="tag" taget="_blank" href="/search/oracle/1.htm">oracle</a> <div>关键字:Oracle实现类split函数的方 项目里需要保存结构数据,批量传到后他进行保存,为了减小数据量,子集拼装的格式,使用存储过程进行保存。保存的过程中需要对数据解析。但是oracle没有Java中split类似的函数。从网上找了一个,也补全了一下。 CREATE OR REPLACE TYPE t_split_100 IS TABLE OF VARCHAR2(100); cr</div> </li> </ul> </div> </div> </div> <div> <div class="container"> <div class="indexes"> <strong>按字母分类:</strong> <a href="/tags/A/1.htm" target="_blank">A</a><a href="/tags/B/1.htm" target="_blank">B</a><a href="/tags/C/1.htm" target="_blank">C</a><a href="/tags/D/1.htm" target="_blank">D</a><a href="/tags/E/1.htm" target="_blank">E</a><a href="/tags/F/1.htm" target="_blank">F</a><a href="/tags/G/1.htm" target="_blank">G</a><a href="/tags/H/1.htm" target="_blank">H</a><a href="/tags/I/1.htm" target="_blank">I</a><a href="/tags/J/1.htm" target="_blank">J</a><a href="/tags/K/1.htm" target="_blank">K</a><a href="/tags/L/1.htm" target="_blank">L</a><a href="/tags/M/1.htm" target="_blank">M</a><a href="/tags/N/1.htm" target="_blank">N</a><a href="/tags/O/1.htm" target="_blank">O</a><a href="/tags/P/1.htm" target="_blank">P</a><a href="/tags/Q/1.htm" target="_blank">Q</a><a href="/tags/R/1.htm" target="_blank">R</a><a href="/tags/S/1.htm" target="_blank">S</a><a href="/tags/T/1.htm" target="_blank">T</a><a href="/tags/U/1.htm" target="_blank">U</a><a href="/tags/V/1.htm" target="_blank">V</a><a href="/tags/W/1.htm" target="_blank">W</a><a href="/tags/X/1.htm" target="_blank">X</a><a href="/tags/Y/1.htm" target="_blank">Y</a><a href="/tags/Z/1.htm" target="_blank">Z</a><a href="/tags/0/1.htm" target="_blank">其他</a> </div> </div> </div> <footer id="footer" class="mb30 mt30"> <div class="container"> <div class="footBglm"> <a target="_blank" href="/">首页</a> - <a target="_blank" href="/custom/about.htm">关于我们</a> - <a target="_blank" href="/search/Java/1.htm">站内搜索</a> - <a target="_blank" href="/sitemap.txt">Sitemap</a> - <a target="_blank" href="/custom/delete.htm">侵权投诉</a> </div> <div class="copyright">版权所有 IT知识库 CopyRight © 2000-2050 E-COM-NET.COM , All Rights Reserved. <!-- <a href="https://beian.miit.gov.cn/" rel="nofollow" target="_blank">京ICP备09083238号</a><br>--> </div> </div> </footer> <!-- 代码高亮 --> <script type="text/javascript" src="/static/syntaxhighlighter/scripts/shCore.js"></script> <script type="text/javascript" src="/static/syntaxhighlighter/scripts/shLegacy.js"></script> <script type="text/javascript" src="/static/syntaxhighlighter/scripts/shAutoloader.js"></script> <link type="text/css" rel="stylesheet" href="/static/syntaxhighlighter/styles/shCoreDefault.css"/> <script type="text/javascript" src="/static/syntaxhighlighter/src/my_start_1.js"></script> </body> </html>