var http_request=false;
var isFlag=false;
if(window.XMLHttpRequest)
{//Mozilla,Safari,...
     http_request=new XMLHttpRequest();
	 isFlag=true;
     if(http_request.overrideMimeType)
	 {
     	http_request.overrideMimeType('text/xml');
  	 }
}
else if(window.ActiveXObject)
{//IE
   try
   {
   		http_request=new ActiveXObject("Msxml2.XMLHTTP");
   }
   catch(e)
   {
   		try
		{
 			http_request=new ActiveXObject("Microsoft.XMLHTTP");
 		}
		catch(e)
		{}
 	}
 }
 if(!http_request)
 {
 	alert('Giving up:(Cannot create an XMLHTTP instance)');

 }


var regetext="";
var url="/AjaxArray.aspx";

http_request.open("GET",url,isFlag);

//firfox不支持 http_request.open("GET",url,false);语句
//IE不支持http_request.open("GET",url,true);语句

http_request.onreadystatechange=GetKeyAdList;
http_request.send(null);
function GetKeyAdList()
 {
	
   if(http_request.readyState == 4)
    {
        if (http_request.status == 200)
        {   
            var str=http_request.responseText;
            regetext=str;
			//alert(regetext+"1111");
			cha_init("content",regetext);
        }
        else if (http_request.status == 404)
        {
            alert("Request URL does not exist");
        }
        else
        {
            alert("Error: status code is " + http_request.status);
        }
      }
 }

//cha_init("content",regetext);  firfox不支持此调用