常用js代码

// JavaScript Document//获取cookiefunction getCookie( name ) {    var start = document.cookie.indexOf( name + "=" );    var len = start + name.length + 1;    if ( ( !start ) && ( name != document.cookie.substring( 0, name.length ) ) ) {        return null;    }    if ( start == -1 ) return null;    var end = document.cookie.indexOf( ';', len );    if ( end == -1 ) end = document.cookie.length;    return unescape( document.cookie.substring( len, end ) );}//设置cookiefunction setCookie( name, value, expires, path, domain, secure ) {    var today = new Date();    today.setTime( today.getTime() );    if ( expires ) {        expires = expires * 1000 * 60 * 60 * 24;    }    var expires_date = new Date( today.getTime() + (expires) );    document.cookie = name+'='+escape( value ) +        ( ( expires ) ? ';expires='+expires_date.toGMTString() : '' ) + //expires.toGMTString()        ( ( path ) ? ';path=' + path : '' ) +        ( ( domain ) ? ';domain=' + domain : '' ) +        ( ( secure ) ? ';secure' : '' );}//删除cookiefunction deleteCookie( name, path, domain ) {    if ( getCookie( name ) ) document.cookie = name + '=' +            ( ( path ) ? ';path=' + path : '') +            ( ( domain ) ? ';domain=' + domain : '' ) +            ';expires=Thu, 01-Jan-1970 00:00:01 GMT';}//设置样式function setStyle(el,prop,value){   if(prop == "opacity" && !+"\v1"){     //IE7 bug:filter 滤镜要求 hasLayout=true 方可执行（否则没有效果）     if (!el.currentStyle || !el.currentStyle.hasLayout) el.style.zoom = 1;     prop = "filter";     if(!!window.XDomainRequest){       value ="progid:DXImageTransform.Microsoft.Alpha(style=0,opacity="+value*100+")";     }else{       value ="alpha(opacity="+value*100+")"     }   }   el.style.cssText += ';' + (prop+":"+value); } //获取样式 function getStyle(el, style){   if(!+"\v1"){     style = style.replace(/\-(\w)/g, function(all, letter){       return letter.toUpperCase();     });     return el.currentStyle[style];   }else{     return document.defaultView.getComputedStyle(el, null).getPropertyValue(style)   } } //获取id function $() {    var elements = [];    for (var i = 0; i < arguments.length; i++) {        var element = arguments[i];        if (typeof element == 'string')            element = document.getElementById(element);        if (arguments.length == 1)            return element;        elements.push(element);    }    return elements;}//添加事件function addEvent(elm, evType, fn, useCapture) {  if (elm.addEventListener) {    elm.addEventListener(evType, fn, useCapture);//DOM2.0    return true;  }  else if (elm.attachEvent) {    var r = elm.attachEvent('on' + evType, fn);//IE5+    return r;  }  else {    elm['on' + evType] = fn;//DOM 0  }}//移除事件function removeEvent(elm, evType, fn, useCapture) {  if (elm.removeEventListener) {    elm.removeEventListener(evType, fn, useCapture);//DOM2.0    return true;  }  else if (elm.detachEvent) {    var r = elm.detachEvent('on' + evType, fn);//IE5+    return r;  }  else {    elm['on' + evType] = fn;//DOM 0  }}