ajax 获得页面的相应时间 支持ie 和ff
<html><title>无标题页</title><script type="text/javascript">function $(name){return document.getElementById(name);}function GetXmlHttpObject(){var xmlRequest; try{ if(window.ActiveXObject) { var MSXML = new Array('MSXML2.XMLHTTP','Microsoft.XMLHTTP','MSXML2.XMLHTTP.3.0','MSXML2.XMLHTTP.4.0','MSXML2.XMLHTTP.5.0'); for(var i=0;i<MSXML.length;i++) { try { xmlRequest = new ActiveXObject(MSXML[i]); break; } catch(e) { xmlRequest = null; } } } else if(window.XMLHttpRequest) { xmlRequest = new XMLHttpRequest(); if(xmlRequest.overrideMimeType) { xmlRequest.overrideMimeType('text/xml'); } } if(xmlRequest == null) { // 异常，创建对象实例失败 window.alert("不能创建XMLHttpRequest对象实例."); return false; } } catch(e){} return xmlRequest;}function ajaxTest(){xmlHttp = GetXmlHttpObject();if(xmlHttp==null)alert("error!!!!");xmlHttp.open("GET","http://www.google.com.hk/",true);xmlHttp.onreadystatechange=stateChanged;xmlHttp.send(null);}var time1;var time2;function stateChanged(){if(xmlHttp==null)alert("error!!!!");if (xmlHttp.readyState==1){$("text1").innerHTML="Loading...";time1=new Date();}if (xmlHttp.readyState==4){time2=new Date();var n=time2.getTime()-time1.getTime();$("text1").innerHTML=("response time:"+n+"ms");}}</script></head><body><input id="Button1" type="button" value="AJAX" onclick="ajaxTest()" /></div><div id="text1" style="width: 500px; height: 100px;"></body></html>?