前端学习——Vue (Day1)
Vue 快速上手
Vue 是什么
创建 Vue 实例
Vue2官网：https://v2.cn.vuejs.org/
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<!--
创建Vue实例，初始化渲染
1. 准备容器
2. 引包（开发版本包 / 生产版本包）官网
3. 创建实例
4. 添加配置项 => 完成渲染
-->
<div class="box2"></div>
<div class="box"></div>
<div id="app">
<!-- 此处将来会编写一些用于渲染的逻辑代码 -->
<h1>{{ msg }}</h1>
<a href="">{{ count }}</a>
</div>
<!-- 引包（开发版本，包括完整注释和警告） -->
<!-- <script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/vue.js"></script> -->
<script src="vue.js"></script>
<!-- 创建实例 -->
<script>
// 一旦引入VueJS核心包，就有了 Vue 构造函数
const app = new Vue({
// 通过 el 配置选择器，指定 Vue 管理的是哪个盒子
el: '#app',
// 通过 data 提供数据
data: {
msg: 'Hello 八月长安',
count: 666
}
})
</script>
</body>
</html>
插值表达式 {{ }}
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<!-- 插值表达式：Vue的一种模板语法
作用：利用表达式 进行插值渲染
语法：{{ 表达式 }}
注意：
1. 使用的数据要存在
2. 支持表达式（不支持if for）
3. 不能再标签属性中使用{{ }}
-->
<div id="app">
<p>{{ nickname }}</p>
<p>{{ nickname.toUpperCase() }}</p>
<p>{{ nickname + '你好' }}</p>
<p>{{ age >= 18 ? '成年' : '未成年' }}</p>
<p>{{ friend.name }}</p>
<p>{{ friend.desc }}</p>
</div>
<script src="vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
nickname: 'tony',
age: 18,
friend:{
name: 'jackson',
desc: '热爱学习'
}
}
})
</script>
</body>
</html>
Vue 核心特性：响应式
Vue 指令
v-html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<div v-html="msg"></div>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
msg: `
走进八月长安笔下的振华中学
`
}
})
</script>
</body>
</html>
v-show VS v-if
v-else VS v-else-if
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<p v-if="gender === 1">性别：♂ 男</p>
<p v-else>性别：♀ 女</p>
<hr>
<p v-if="score >= 90" >成绩评定A：奖励电脑一台</p>
<p v-else-if="score >= 70">成绩评定B：奖励周末郊游</p>
<p v-else-if="score >= 60">成绩评定C：奖励零食礼包</p>
<p v-else>成绩评定D：惩罚一周不能玩手机</p>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
gender: 1,
score: 80
}
})
</script>
</body>
</html>
v-on
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<button @click="count--">-</button>
<span>{{ count }}</span>
<button v-on:click="count++">+</button>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
count: 100
}
})
</script>
</body>
</html>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<button @click="fn">切换显示隐藏</button>
<h1 v-show="isShow">霍格沃茨</h1>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
isShow: true
},
methods: {
fn() {
// 让提供的所有methods中的函数，this都指向当前实例
this.isShow = !this.isShow
}
}
})
</script>
</body>
</html>
v-on 调用传参
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
.box {
border: 3px solid #000000;
border-radius: 10px;
padding: 20px;
margin: 20px;
width: 200px;
}
h3 {
margin: 10px 0 20px 0;
}
p {
margin: 20px;
}
</style>
</head>
<body>
<div id="app">
<div class="box">
<h3>小黑自动售货机</h3>
<button @click="buy(cola)">可乐5元</button>
<button @click="buy(coffee)">咖啡10元</button>
</div>
<p>银行卡余额：{{ money }}元</p>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
money: 1000,
cola: 5,
coffee: 10
},
methods: {
buy(pri) {
this.money -= pri
},
}
})
</script>
</body>
</html>
v-bind
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<img v-bind:src="imgUrl" v-bind:title="msg" alt="">
<img :src="imgUrl" :title="msg" alt="">
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
imgUrl: './Vue/01-随堂代码&素材/day01/准备代码/imgs/10-01.png',
msg: '哈喽，波仔'
}
})
</script>
</body>
</html>
案例
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<button v-show="index > 0" @click="index--">上一页</button>
<div>
<img :src="list[index]" alt="">
</div>
<button v-show="index < list.length - 1" @click="index++">下一页</button>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
index: 0,
list: [
'./Vue/01-随堂代码&素材/day01/准备代码/imgs/11-00.gif',
'./Vue/01-随堂代码&素材/day01/准备代码/imgs/11-01.gif',
'./Vue/01-随堂代码&素材/day01/准备代码/imgs/11-02.gif',
'./Vue/01-随堂代码&素材/day01/准备代码/imgs/11-03.gif',
'./Vue/01-随堂代码&素材/day01/准备代码/imgs/11-04.png',
'./Vue/01-随堂代码&素材/day01/准备代码/imgs/11-05.png',
]
}
})
</script>
</body>
</html>
v-for
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<h3>小黑水果店</h3>
<ul>
<li v-for="(item,index) in list">{{ item }}-{{ index }}</li>
</ul>
<ul>
<li v-for="item in list">{{ item }}</li>
</ul>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
list: ['西瓜', '苹果', '鸭梨']
}
})
</script>
</body>
</html>
案例
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<h3>小黑的书架</h3>
<ul>
<li v-for="(item,index) in booksList" :key="item.id">
<span>{{ item.name }} </span>
<span>{{ item.author }} </span>
<!-- 注册点击事件 ， 通过id删除数组中对象 -->
<button @click="del(item.id)">删除</button>
</li>
</ul>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
booksList: [
{ id: 1, name: '《红楼梦》', author: '曹雪芹' },
{ id: 2, name: '《西游记》', author: '吴承恩' },
{ id: 3, name: '《水浒传》', author: '施耐庵' },
{ id: 4, name: '《三国演义》', author: '罗贯中' }
]
},
methods: {
del(id) {
// 通过id进行删除数组中的对应项 -> filter
// filter：根据条件，保留满足条件的对应项，得到一个新数组
this.booksList = this.booksList.filter(item => item.id !== id)
}
}
})
</script>
</body>
</html>
v-for 中的 key
v-model
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="app">
<!--
v-model 可以让数据和视图形成双向数据绑定
① 数据变化 → 视图自动更新
② 视图变化 → 数据自动更新
可以快读获取或设置表单元素内容
-->
账户：<input type="text" v-model="username"> <br><br>
密码：<input type="password" v-model="password"> <br><br>
<button @click="login">登录</button>
<button @click="reset">重置</button>
</div>
<script src="./vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
username:'',
password:''
},
methods: {
login(){
console.log(this.username,this.password);
},
reset(){
this.username=''
this.password=''
}
}
})
</script>
</body>
</html>
综合案例 - 小黑记事本
在这里插入代码片
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>记事本</title>
<style>
html,
body {
margin: 0;
padding: 0;
}
body {
background: #fff;
}
button {
margin: 0;
padding: 0;
border: 0;
background: none;
font-size: 100%;
vertical-align: baseline;
font-family: inherit;
font-weight: inherit;
color: inherit;
-webkit-appearance: none;
appearance: none;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
}
body {
font: 14px 'Helvetica Neue', Helvetica, Arial, sans-serif;
line-height: 1.4em;
background: #f5f5f5;
color: #4d4d4d;
min-width: 230px;
max-width: 550px;
margin: 0 auto;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
font-weight: 300;
}
:focus {
outline: 0;
}
.hidden {
display: none;
}
#app {
background: #fff;
margin: 180px 0 40px 0;
padding: 15px;
position: relative;
box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.2), 0 25px 50px 0 rgba(0, 0, 0, 0.1);
}
#app .header input {
border: 2px solid rgba(175, 47, 47, 0.8);
border-radius: 10px;
}
#app .add {
position: absolute;
right: 15px;
top: 15px;
height: 68px;
width: 140px;
text-align: center;
background-color: rgba(175, 47, 47, 0.8);
color: #fff;
cursor: pointer;
font-size: 18px;
border-radius: 0 10px 10px 0;
}
#app input::-webkit-input-placeholder {
font-style: italic;
font-weight: 300;
color: #e6e6e6;
}
#app input::-moz-placeholder {
font-style: italic;
font-weight: 300;
color: #e6e6e6;
}
#app input::input-placeholder {
font-style: italic;
font-weight: 300;
color: gray;
}
#app h1 {
position: absolute;
top: -120px;
width: 100%;
left: 50%;
transform: translateX(-50%);
font-size: 60px;
font-weight: 100;
text-align: center;
color: rgba(175, 47, 47, 0.8);
-webkit-text-rendering: optimizeLegibility;
-moz-text-rendering: optimizeLegibility;
text-rendering: optimizeLegibility;
}
.new-todo,
.edit {
position: relative;
margin: 0;
width: 100%;
font-size: 24px;
font-family: inherit;
font-weight: inherit;
line-height: 1.4em;
border: 0;
color: inherit;
padding: 6px;
box-shadow: inset 0 -1px 5px 0 rgba(0, 0, 0, 0.2);
box-sizing: border-box;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
}
.new-todo {
padding: 16px;
border: none;
background: rgba(0, 0, 0, 0.003);
box-shadow: inset 0 -2px 1px rgba(0, 0, 0, 0.03);
}
.main {
position: relative;
z-index: 2;
}
.todo-list {
margin: 0;
padding: 0;
list-style: none;
overflow: hidden;
}
.todo-list li {
position: relative;
font-size: 24px;
height: 60px;
box-sizing: border-box;
border-bottom: 1px solid #e6e6e6;
}
.todo-list li:last-child {
border-bottom: none;
}
.todo-list .view .index {
position: absolute;
color: gray;
left: 10px;
top: 20px;
font-size: 22px;
}
.todo-list li .toggle {
text-align: center;
width: 40px;
/* auto, since non-WebKit browsers doesn't support input styling */
height: auto;
position: absolute;
top: 0;
bottom: 0;
margin: auto 0;
border: none;
/* Mobile Safari */
-webkit-appearance: none;
appearance: none;
}
.todo-list li .toggle {
opacity: 0;
}
.todo-list li .toggle+label {
/*
Firefox requires `#` to be escaped - https://bugzilla.mozilla.org/show_bug.cgi?id=922433
IE and Edge requires *everything* to be escaped to render, so we do that instead of just the `#` - https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/7157459/
*/
background-image: url('data:image/svg+xml;utf8,%3Csvg%20xmlns%3D%22http%3A//www.w3.org/2000/svg%22%20width%3D%2240%22%20height%3D%2240%22%20viewBox%3D%22-10%20-18%20100%20135%22%3E%3Ccircle%20cx%3D%2250%22%20cy%3D%2250%22%20r%3D%2250%22%20fill%3D%22none%22%20stroke%3D%22%23ededed%22%20stroke-width%3D%223%22/%3E%3C/svg%3E');
background-repeat: no-repeat;
background-position: center left;
}
.todo-list li .toggle:checked+label {
background-image: url('data:image/svg+xml;utf8,%3Csvg%20xmlns%3D%22http%3A//www.w3.org/2000/svg%22%20width%3D%2240%22%20height%3D%2240%22%20viewBox%3D%22-10%20-18%20100%20135%22%3E%3Ccircle%20cx%3D%2250%22%20cy%3D%2250%22%20r%3D%2250%22%20fill%3D%22none%22%20stroke%3D%22%23bddad5%22%20stroke-width%3D%223%22/%3E%3Cpath%20fill%3D%22%235dc2af%22%20d%3D%22M72%2025L42%2071%2027%2056l-4%204%2020%2020%2034-52z%22/%3E%3C/svg%3E');
}
.todo-list li label {
word-break: break-all;
padding: 15px 15px 15px 60px;
display: block;
line-height: 1.2;
transition: color 0.4s;
}
.todo-list li.completed label {
color: #d9d9d9;
text-decoration: line-through;
}
.todo-list li .destroy {
display: none;
position: absolute;
top: 0;
right: 10px;
bottom: 0;
width: 40px;
height: 40px;
margin: auto 0;
font-size: 30px;
color: #cc9a9a;
margin-bottom: 11px;
transition: color 0.2s ease-out;
}
.todo-list li .destroy:hover {
color: #af5b5e;
}
.todo-list li .destroy:after {
content: '×';
}
.todo-list li:hover .destroy {
display: block;
}
.todo-list li .edit {
display: none;
}
.todo-list li.editing:last-child {
margin-bottom: -1px;
}
.footer {
color: #777;
padding: 10px 15px;
height: 20px;
text-align: center;
border-top: 1px solid #e6e6e6;
}
.footer:before {
content: '';
position: absolute;
right: 0;
bottom: 0;
left: 0;
height: 50px;
overflow: hidden;
box-shadow: 0 1px 1px rgba(0, 0, 0, 0.2), 0 8px 0 -3px #f6f6f6,
0 9px 1px -3px rgba(0, 0, 0, 0.2), 0 16px 0 -6px #f6f6f6,
0 17px 2px -6px rgba(0, 0, 0, 0.2);
}
.todo-count {
float: left;
text-align: left;
}
.todo-count strong {
font-weight: 300;
}
.filters {
margin: 0;
padding: 0;
list-style: none;
position: absolute;
right: 0;
left: 0;
}
.filters li {
display: inline;
}
.filters li a {
color: inherit;
margin: 3px;
padding: 3px 7px;
text-decoration: none;
border: 1px solid transparent;
border-radius: 3px;
}
.filters li a:hover {
border-color: rgba(175, 47, 47, 0.1);
}
.filters li a.selected {
border-color: rgba(175, 47, 47, 0.2);
}
.clear-completed,
html .clear-completed:active {
float: right;
position: relative;
line-height: 20px;
text-decoration: none;
cursor: pointer;
}
.clear-completed:hover {
text-decoration: underline;
}
.info {
margin: 50px auto 0;
color: #bfbfbf;
font-size: 15px;
text-shadow: 0 1px 0 rgba(255, 255, 255, 0.5);
text-align: center;
}
.info p {
line-height: 1;
}
.info a {
color: inherit;
text-decoration: none;
font-weight: 400;
}
.info a:hover {
text-decoration: underline;
}
/*
Hack to remove background from Mobile Safari.
Can't use it globally since it destroys checkboxes in Firefox
*/
@media screen and (-webkit-min-device-pixel-ratio: 0) {
.toggle-all,
.todo-list li .toggle {
background: none;
}
.todo-list li .toggle {
height: 40px;
}
}
@media (max-width: 430px) {
.footer {
height: 50px;
}
.filters {
bottom: 10px;
}
}
</style>
</head>
<body>
<!-- 主体区域 -->
<section id="app">
<!-- 输入框 -->
<header class="header">
<h1>小黑记事本</h1>
<input v-model="todoName" placeholder="请输入任务" class="new-todo" />
<button @click="add" class="add">添加任务</button>
</header>
<!-- 列表区域 -->
<section class="main">
<ul class="todo-list">
<li class="todo" v-for="(item,index) in list" :key="item.id">
<div class="view">
<span class="index">{{ index+1 }}</span> <label>{{ item.name }}</label>
<button @click="del(item.id)" class="destroy"></button>
</div>
</li>
</ul>
</section>
<!-- 统计和清空 (如果没有任务隐藏，v-show)-->
<footer class="footer" v-show="list.length > 0">
<!-- 统计 -->
<span class="todo-count">合 计:<strong> {{ list.length }} </strong></span>
<!-- 清空 -->
<button @click="clear" class="clear-completed">
清空任务
</button>
</footer>
</section>
<!-- 底部 -->
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<script>
// 添加功能
// 1. 通过v-model绑定输入框，实时获取表单元素内容
// 2. 点击按钮，进行新增，往数组最前面加 unshift
const app = new Vue({
el: '#app',
data: {
todoName: '',
list: [
{ id: 1, name: '跑步3公里' },
{ id: 2, name: '游泳1000米' },
{ id: 3, name: '跳绳200次' },
]
},
methods: {
del(id) {
this.list = this.list.filter(item => item.id !== id)
},
add() {
if(this.todoName.trim() === ''){
alert('请输入任务：')
return
}
this.list.unshift({
id: +new Date(),
name: this.todoName
})
this.todoName=''
},
clear(){
this.list = []
}
}
})
</script>
</body>
</html>
