JavaScript技巧收集(1)
1、原生JavaScript实现字符串长度截取
function cutstr(str, len) {
var temp;
var icount = 0;
var patrn = /[^\x00-\xff]/;
var strre = "";
for (var i = 0; i < str.length; i++) {
if (icount < len - 1) {
temp = str.substr(i, 1);
if (patrn.exec(temp) == null) {
icount = icount + 1
} else {
icount = icount + 2
}
strre += temp
} else {
break
}
}
return strre + "..."
}
2、原生JavaScript获取域名主机
function getHost(url) {
var host = "null";
if(typeof url == "undefined"|| null == url) {
url = window.location.href;
}
var regex = /^\w+\:\/\/([^\/]*).*/;
var match = url.match(regex);
if(typeof match != "undefined" && null != match) {
host = match[1];
}
return host;
}
3、原生JavaScript清除空格
String.prototype.trim = function() {
var reExtraSpace = /^\s*(.*?)\s+$/;
returnthis.replace(reExtraSpace, "$1")
}
4、原生JavaScript替换全部
String.prototype.replaceAll = function(s1, s2) {
returnthis.replace(new RegExp(s1, "gm"), s2)
}
5、原生JavaScript转义html标签
function HtmlEncode(text) {
return text.replace(/&/g, '&').replace(/\"/g, '"').replace(/</g, '<').replace(/>/g, '>')
}
7、原生JavaScript时间日期格式转换
Date.prototype.Format = function(formatStr) {
var str = formatStr;
var Week = ['日', '一', '二', '三', '四', '五', '六'];
str = str.replace(/yyyy|YYYY/, this.getFullYear());
str = str.replace(/yy|YY/, (this.getYear() % 100) > 9 ? (this.getYear() % 100).toString() : '0' + (this.getYear() % 100));
str = str.replace(/MM/, (this.getMonth() + 1) > 9 ? (this.getMonth() + 1).toString() : '0' + (this.getMonth() + 1));
str = str.replace(/M/g, (this.getMonth() + 1));
str = str.replace(/w|W/g, Week[this.getDay()]);
str = str.replace(/dd|DD/, this.getDate() > 9 ? this.getDate().toString() : '0' + this.getDate());
str = str.replace(/d|D/g, this.getDate());
str = str.replace(/hh|HH/, this.getHours() > 9 ? this.getHours().toString() : '0' + this.getHours());
str = str.replace(/h|H/g, this.getHours());
str = str.replace(/mm/, this.getMinutes() > 9 ? this.getMinutes().toString() : '0' + this.getMinutes());
str = str.replace(/m/g, this.getMinutes());
str = str.replace(/ss|SS/, this.getSeconds() > 9 ? this.getSeconds().toString() : '0' + this.getSeconds());
str = str.replace(/s|S/g, this.getSeconds());
return str
}
8、原生JavaScript判断是否为数字类型
function isDigit(value) {
var patrn = /^[0-9]*$/;
if (patrn.exec(value) == null || value == "") {
returnfalse
} else {
returntrue
}
}
9、原生JavaScript设置cookie值
function setCookie(name, value, Hours) {
var d = new Date();
var offset = 8;
var utc = d.getTime() + (d.getTimezoneOffset() * 60000);
var nd = utc + (3600000 * offset);
var exp = new Date(nd);
exp.setTime(exp.getTime() + Hours * 60 * 60 * 1000);
document.cookie = name + "=" + escape(value) + ";path=/;expires=" + exp.toGMTString() + ";domain=360doc.com;"
}
10、原生JavaScript获取cookie值
function getCookie(name) {
var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)"));
if (arr != null) return unescape(arr[2]);
returnnull
}
11、原生JavaScript加入收藏夹
function AddFavorite(sURL, sTitle) {
try {
window.external.addFavorite(sURL, sTitle)
} catch(e) {
try {
window.sidebar.addPanel(sTitle, sURL, "")
} catch(e) {
alert("加入收藏失败，请使用Ctrl+D进行添加")
}
}
}
12、原生JavaScript设为首页
function setHomepage() {
if (document.all) {
document.body.style.behavior = 'url(#default#homepage)';
document.body.setHomePage('http://www.jq-school.com')
} elseif (window.sidebar) {
if (window.netscape) {
try {
netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect")
} catch(e) {
alert("该操作被浏览器拒绝，如果想启用该功能，请在地址栏内输入 about:config,然后将项 signed.applets.codebase_principal_support 值该为true")
}
}
var prefs = Components.classes['@mozilla.org/preferences-service;1'].getService(Components.interfaces.nsIPrefBranch);
prefs.setCharPref('browser.startup.homepage', 'http://www.jq-school.com')
}
}
13、原生JavaScript判断IE6
var ua = navigator.userAgent.toLowerCase();
var isIE6 = ua.indexOf("msie 6") > -1;
if (isIE6) {
try {
document.execCommand("BackgroundImageCache", false, true)
} catch(e) {}
}
14、原生JavaScript加载样式文件
function LoadStyle(url) {
try {
document.createStyleSheet(url)
} catch(e) {
var cssLink = document.createElement('link');
cssLink.rel = 'stylesheet';
cssLink.type = 'text/css';
cssLink.href = url;
var head = document.getElementsByTagName('head')[0];
head.appendChild(cssLink)
}
}
15、原生JavaScript返回脚本内容
function evalscript(s) {
if(s.indexOf('<script') == -1) return s;
var p = /<script[^\>]*?>([^\x00]*?)<\/script>/ig;
var arr = [];
while(arr = p.exec(s)) {
var p1 = /<script[^\>]*?src=\"([^\>]*?)\"[^\>]*?(reload=\"1\")?(?:charset=\"([\w\-]+?)\")?><\/script>/i;
var arr1 = [];
arr1 = p1.exec(arr[0]);
if(arr1) {
appendscript(arr1[1], '', arr1[2], arr1[3]);
} else {
p1 = /<script(.*?)>([^\x00]+?)<\/script>/i;
arr1 = p1.exec(arr[0]);
appendscript('', arr1[2], arr1[1].indexOf('reload=') != -1);
}
}
return s;
}
16、原生JavaScript清除脚本内容
function stripscript(s) {
return s.replace(/<script.*?>.*?<\/script>/ig, '');
}
17、原生JavaScript动态加载脚本文件
function appendscript(src, text, reload, charset) {
var id = hash(src + text);
if(!reload && in_array(id, evalscripts)) return;
if(reload && $(id)) {
$(id).parentNode.removeChild($(id));
}
evalscripts.push(id);
var scriptNode = document.createElement("script");
scriptNode.type = "text/javascript";
scriptNode.id = id;
scriptNode.charset = charset ? charset : (BROWSER.firefox ? document.characterSet : document.charset);
try {
if(src) {
scriptNode.src = src;
scriptNode.onloadDone = false;
scriptNode.onload = function () {
scriptNode.onloadDone = true;
JSLOADED[src] = 1;
};
scriptNode.onreadystatechange = function () {
if((scriptNode.readyState == 'loaded' || scriptNode.readyState == 'complete') && !scriptNode.onloadDone) {
scriptNode.onloadDone = true;
JSLOADED[src] = 1;
}
};
} elseif(text){
scriptNode.text = text;
}
document.getElementsByTagName('head')[0].appendChild(scriptNode);
} catch(e) {}
}
18、原生JavaScript返回按ID检索的元素对象
function $(id) {
return !id ? null : document.getElementById(id);
}
19、原生JavaScript返回浏览器版本内容
function browserVersion(types) {
var other = 1;
for(i in types) {
var v = types<i> ? types<i> : i;
if(USERAGENT.indexOf(v) != -1) {
var re = new RegExp(v + '(\\/|\\s)([\\d\\.]+)', 'ig');
var matches = re.exec(USERAGENT);
var ver = matches != null ? matches[2] : 0;
other = ver !== 0 && v != 'mozilla' ? 0 : other;
}else {
var ver = 0;
}
eval('BROWSER.' + i + '= ver');
}
BROWSER.other = other;
}
20、原生JavaScript元素显示的通用方法
function $(id) {
return !id ? null : document.getElementById(id);
}
function display(id) {
var obj = $(id);
if(obj.style.visibility) {
obj.style.visibility = obj.style.visibility == 'visible' ? 'hidden' : 'visible';
} else {
obj.style.display = obj.style.display == '' ? 'none' : '';
}
}
21、原生JavaScript中有insertBefore方法,可惜却没有insertAfter方法?用如下函数实现
function insertAfter(newChild,refChild){
var parElem=refChild.parentNode;
if(parElem.lastChild==refChild){
refChild.appendChild(newChild);
}else{
parElem.insertBefore(newChild,refChild.nextSibling);
}
}
22、原生JavaScript中兼容浏览器绑定元素事件
function addEventSamp(obj,evt,fn){
if (obj.addEventListener) {
obj.addEventListener(evt, fn, false);
}elseif(obj.attachEvent){
obj.attachEvent('on'+evt,fn);
}
}
23、原生JavaScript光标停在文字的后面，文本框获得焦点时调用
function focusLast(){
var e = event.srcElement;
var r =e.createTextRange();
r.moveStart('character',e.value.length);
r.collapse(true);
r.select();
}
24、原生JavaScript检验URL链接是否有效
function getUrlState(URL){
var xmlhttp = new ActiveXObject("microsoft.xmlhttp");
xmlhttp.Open("GET",URL, false);
try{
xmlhttp.Send();
}catch(e){
}finally{
var result = xmlhttp.responseText;
if(result){
if(xmlhttp.Status==200){
return(true);
}else{
return(false);
}
}else{
return(false);
}
}
}
25、原生JavaScript格式化CSS样式代码
function formatCss(s){//格式化代码
s = s.replace(/\s*([\{\}\:\;\,])\s*/g, "$1");
s = s.replace(/;\s*;/g, ";"); //清除连续分号
s = s.replace(/\,[\s\.\#\d]*{/g, "{");
s = s.replace(/([^\s])\{([^\s])/g, "$1 {\n\t$2");
s = s.replace(/([^\s])\}([^\n]*)/g, "$1\n}\n$2");
s = s.replace(/([^\s]);([^\s\}])/g, "$1;\n\t$2");
return s;
}
26、原生JavaScript压缩CSS样式代码
function yasuoCss (s) {//压缩代码
s = s.replace(/\/\*(.|\n)*?\*\//g, ""); //删除注释
s = s.replace(/\s*([\{\}\:\;\,])\s*/g, "$1");
s = s.replace(/\,[\s\.\#\d]*\{/g, "{"); //容错处理
s = s.replace(/;\s*;/g, ";"); //清除连续分号
s = s.match(/^\s*(\S+(\s+\S+)*)\s*$/); //去掉首尾空白
return (s == null) ? "" : s[1];
}
27、原生JavaScript获取当前路径
var currentPageUrl = "";
if (typeofthis.href === "undefined") {
currentPageUrl = document.location.toString().toLowerCase();
}
else {
currentPageUrl = this.href.toString().toLowerCase();
}
28、原生JavaScriptIP转成整型
function _ip2int(ip){
var num = 0;
ip = ip.split(".");
num = Number(ip[0]) * 256 * 256 * 256 + Number(ip[1]) * 256 * 256 + Number(ip[2]) * 256 + Number(ip[3]);
num = num >>> 0;
return num;
}
29、原生JavaScript整型解析为IP地址
function _int2iP(num){
var str;
var tt = new Array();
tt[0] = (num >>> 24) >>> 0;
tt[1] = ((num << 8) >>> 24) >>> 0;
tt[2] = (num << 16) >>> 24;
tt[3] = (num << 24) >>> 24;
str = String(tt[0]) + "." + String(tt[1]) + "." + String(tt[2]) + "." + String(tt[3]);
return str;
}
30、原生JavaScript实现checkbox全选与全不选
function checkAll() {
var selectall = document.getElementById("selectall");
var allbox = document.getElementsByName("allbox");
if (selectall.checked) {
for (var i = 0; i < allbox.length; i++) {
allbox.checked = true;
}
} else {
for (var i = 0; i < allbox.length; i++) {
allbox.checked = false;
}
}
}
31、原生JavaScript判断是否移动设备
function isMobile(){
if (typeofthis._isMobile === 'boolean'){
returnthis._isMobile;
}
var screenWidth = this.getScreenWidth();
var fixViewPortsExperiment = rendererModel.runningExperiments.FixViewport || rendererModel.runningExperiments.fixviewport;
var fixViewPortsExperimentRunning = fixViewPortsExperiment && (fixViewPortsExperiment.toLowerCase() === "new");
if(!fixViewPortsExperiment){
if(!this.isAppleMobileDevice()){
screenWidth = screenWidth/window.devicePixelRatio;
}
}
var isMobileScreenSize = screenWidth < 600;
var isMobileUserAgent = false;
this._isMobile = isMobileScreenSize && this.isTouchScreen();
returnthis._isMobile;
}
32、原生JavaScript判断是否移动设备访问
function isAppleMobileDevice(){
return (/iphone|ipod|ipad|Macintosh/i.test(navigator.userAgent.toLowerCase()));
}
33、原生JavaScript判断是否苹果移动设备访问
function isAppleMobileDevice(){
return (/iphone|ipod|ipad|Macintosh/i.test(navigator.userAgent.toLowerCase()));
}
34、原生JavaScript判断是否安卓移动设备访问
function isAndroidMobileDevice(){
return (/android/i.test(navigator.userAgent.toLowerCase()));
}
35、原生JavaScript判断是否Touch屏幕
function isTouchScreen(){
return (('ontouchstart'in window) || window.DocumentTouch && document instanceof DocumentTouch);
}
36、原生JavaScript判断是否在安卓上的谷歌浏览器
function isNewChromeOnAndroid(){
if(this.isAndroidMobileDevice()){
var userAgent = navigator.userAgent.toLowerCase();
if((/chrome/i.test(userAgent))){
var parts = userAgent.split('chrome/');
var fullVersionString = parts[1].split(" ")[0];
var versionString = fullVersionString.split('.')[0];
var version = parseInt(versionString);
if(version >= 27){
returntrue;
}
}
}
returnfalse;
}
37、原生JavaScript判断是否打开视窗
function isViewportOpen() {
return !!document.getElementById('wixMobileViewport');
}
38、原生JavaScript获取移动设备初始化大小
function getInitZoom(){
if(!this._initZoom){
var screenWidth = Math.min(screen.height, screen.width);
if(this.isAndroidMobileDevice() && !this.isNewChromeOnAndroid()){
screenWidth = screenWidth/window.devicePixelRatio;
}
this._initZoom = screenWidth /document.body.offsetWidth;
}
returnthis._initZoom;
}
39、原生JavaScript获取移动设备最大化大小
function getZoom(){
var screenWidth = (Math.abs(window.orientation) === 90) ? Math.max(screen.height, screen.width) : Math.min(screen.height, screen.width);
if(this.isAndroidMobileDevice() && !this.isNewChromeOnAndroid()){
screenWidth = screenWidth/window.devicePixelRatio;
}
var FixViewPortsExperiment = rendererModel.runningExperiments.FixViewport || rendererModel.runningExperiments.fixviewport;
var FixViewPortsExperimentRunning = FixViewPortsExperiment && (FixViewPortsExperiment === "New" || FixViewPortsExperiment === "new");
if(FixViewPortsExperimentRunning){
return screenWidth / window.innerWidth;
}else{
return screenWidth / document.body.offsetWidth;
}
}
40、原生JavaScript获取移动设备屏幕宽度
function getScreenWidth(){
var smallerSide = Math.min(screen.width, screen.height);
var fixViewPortsExperiment = rendererModel.runningExperiments.FixViewport || rendererModel.runningExperiments.fixviewport;
var fixViewPortsExperimentRunning = fixViewPortsExperiment && (fixViewPortsExperiment.toLowerCase() === "new");
if(fixViewPortsExperiment){
if(this.isAndroidMobileDevice() && !this.isNewChromeOnAndroid()){
smallerSide = smallerSide/window.devicePixelRatio;
}
}
return smallerSide;
}
41、原生 JavaScript完美判断是否为网址
function IsURL(strUrl) {
var regular = /^\b(((https?|ftp):\/\/)?[-a-z0-9]+(\.[-a-z0-9]+)*\.(?:com|edu|gov|int|mil|net|org|biz|info|name|museum|asia|coop|aero|[a-z][a-z]|((25[0-5])|(2[0-4]\d)|(1\d\d)|([1-9]\d)|\d))\b(\/[-a-z0-9_:\@&?=+,.!\/~%\$]*)?)$/i
if (regular.test(strUrl)) {
returntrue;
}
else {
returnfalse;
}
}
42、原生JavaScript根据样式名称检索元素对象
function getElementsByClassName(name) {
var tags = document.getElementsByTagName('*') || document.all;
var els = [];
for (var i = 0; i < tags.length; i++) {
if (tags.className) {
var cs = tags.className.split(' ');
for (var j = 0; j < cs.length; j++) {
if (name == cs[j]) {
els.push(tags);
break
}
}
}
}
return els
}
43、原生JavaScript判断是否以某个字符串开头
String.prototype.startWith = function (s) {
returnthis.indexOf(s) == 0
}
44、原生JavaScript判断是否以某个字符串结束
String.prototype.endWith = function (s) {
var d = this.length - s.length;
return (d >= 0 && this.lastIndexOf(s) == d)
}
45、原生JavaScript返回IE浏览器的版本号
function getIE(){
if (window.ActiveXObject){
var v = navigator.userAgent.match(/MSIE ([^;]+)/)[1];
return parseFloat(v.substring(0, v.indexOf(".")))
}
returnfalse
}
46、原生JavaScript获取页面高度
function getPageHeight(){
var g = document, a = g.body, f = g.documentElement, d = g.compatMode == "BackCompat"
? a
: g.documentElement;
return Math.max(f.scrollHeight, a.scrollHeight, d.clientHeight);
}
47、原生JavaScript获取页面scrollLeft
function getPageScrollLeft(){
var a = document;
return a.documentElement.scrollLeft || a.body.scrollLeft;
}
48、原生JavaScript获取页面可视宽度
function getPageViewWidth(){
var d = document, a = d.compatMode == "BackCompat"
? d.body
: d.documentElement;
return a.clientWidth;
}
49、原生JavaScript获取页面宽度
function getPageWidth(){
var g = document, a = g.body, f = g.documentElement, d = g.compatMode == "BackCompat"
? a
: g.documentElement;
return Math.max(f.scrollWidth, a.scrollWidth, d.clientWidth);
}
50、原生JavaScript获取页面scrollTop
function getPageScrollTop(){
var a = document;
return a.documentElement.scrollTop || a.body.scrollTop;
}