Javascript经常使用方法函数收集（一）

 

1.字符串长度截取

function cutstr(str, len) { var temp, icount = 0, patrn = /[^\x00-\xff]/， 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.替换所有

String.prototype.replaceAll = function(s1, s2) { return this.replace(new RegExp(s1, "gm"), s2) }

3.清除空格

String.prototype.trim = function() { var reExtraSpace = /^\s*(.*?)\s+$/; return this.replace(reExtraSpace, "$1") }

4.清除左空格/右空格

function ltrim(s){ return s.replace( /^(\s*|　*)/, ""); } function rtrim(s){ return s.replace( /(\s*|　*)$/, ""); }

5.判断是否以某个字符串开头

String.prototype.startWith = function (s) { return this.indexOf(s) == 0 }

6.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) }

7.转义html标签

function HtmlEncode(text) { return text.replace(/&/g, '&').replace(/\"/g, '"').replace(/</g, '<').replace(/>/g, '>') }

8.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 }

9.判断是否为数字类型

function isDigit(value) { var patrn = /^[0-9]*$/; if (patrn.exec(value) == null || value == "") { return false } else { return true } }

10.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;" }

11.获取cookie值

function getCookie(name) { var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)")); if (arr != null) return unescape(arr[2]); return null }

12.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") } } }

13.设为首页

function setHomepage() { if (document.all) { document.body.style.behavior = 'url(#default#homepage)'; document.body.setHomePage('http://w3cboy.com') } else if (window.sidebar) { if (window.netscape) { try { netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect") } catch(e) { alert("该操做被浏览器拒绝，若是想启用该功能，请在地址栏内输入 about:config,而后将项 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://w3cboy.com') } }

14.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.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.清除脚本内容

function stripscript(s) { return s.replace(/<script.*?>.*?<\/script>/ig, ''); }

17.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; } }; } else if(text){ scriptNode.text = text; } document.getElementsByTagName('head')[0].appendChild(scriptNode); } catch(e) {} }

18.返回按ID检索的元素对象

function $(id) { return !id ? null : document.getElementById(id); }

19.跨浏览器绑定事件

function addEventSamp(obj,evt,fn){ if(!oTarget){return;} if (obj.addEventListener) { obj.addEventListener(evt, fn, false); }else if(obj.attachEvent){ obj.attachEvent('on'+evt,fn); }else{ oTarget["on" + sEvtType] = fn; } }

20.跨浏览器删除事件

function delEvt(obj,evt,fn){ if(!obj){return;} if(obj.addEventListener){ obj.addEventListener(evt,fn,false); }else if(oTarget.attachEvent){ obj.attachEvent("on" + evt,fn); }else{ obj["on" + evt] = fn; } }

21.为元素添加on方法

Element.prototype.on = Element.prototype.addEventListener; NodeList.prototype.on = function (event, fn) {、 []['forEach'].call(this, function (el) { el.on(event, fn); }); return this; };

22.为元素添加trigger方法

Element.prototype.trigger = function (type, data) { var event = document.createEvent('HTMLEvents'); event.initEvent(type, true, true); event.data = data || {}; event.eventName = type; event.target = this; this.dispatchEvent(event); return this; }; NodeList.prototype.trigger = function (event) { []['forEach'].call(this, function (el) { el['trigger'](event); }); return this; };

23.检验URL连接是否有效

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); } } }

24.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; }

25.压缩CSS样式代码

function compressCss (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]; }

26.获取当前路径

var currentPageUrl = ""; if (typeof this.href === "undefined") { currentPageUrl = document.location.toString().toLowerCase(); }else { currentPageUrl = this.href.toString().toLowerCase(); }

27.判断是否移动设备

function isMobile(){ if (typeof this._isMobile === 'boolean'){ return this._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(); return this._isMobile; }

28.判断是否移动设备访问

function isMobileUserAgent(){ return (/iphone|ipod|android.*mobile|windows.*phone|blackberry.*mobile/i.test(window.navigator.userAgent.toLowerCase())); }

29.判断是否苹果移动设备访问

function isAppleMobileDevice(){ return (/iphone|ipod|ipad|Macintosh/i.test(navigator.userAgent.toLowerCase())); }

30.判断是否安卓移动设备访问

function isAndroidMobileDevice(){ return (/android/i.test(navigator.userAgent.toLowerCase())); }