var xmlHttp;
 var ids;
function createXMLHttpRequest()
{
    //判断浏览器类型并创建对象
    //IE
    if (window.ActiveXObject)
    {
        xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
    }
    //FF
    else if (window.XMLHttpRequest)
    {
        xmlHttp = new XMLHttpRequest();
    }
}
            
function ajaxTest(id,url) {
    ids = id;
    createXMLHttpRequest();
    var uri = url+"?ajaxid="+id+"&time="+new Date().getMilliseconds();
   // alert(uri);
    xmlHttp.open("GET", uri, true);
    xmlHttp.onreadystatechange = callback;
    
    xmlHttp.send(null);    
}

function callback(){
//alert(xmlHttp.responseText);
       if(xmlHttp.readyState == 4) {
           
           if(xmlHttp.status==200) {
                  //alert(xmlHttp.responseText);
            //   alert(ids+"ddcontent");
                var content = xmlHttp.responseText.substr(0,xmlHttp.responseText.indexOf("<!"));
                // display data
                document.getElementById(ids+"ddcontent").innerHTML = "<ul>"+content+"</ul>";
                //document.getElementById(ids+"ddcontent").innerHTML = "<ul>"+content+"<li><a href='javascript:void(null)'  class='underline' >sdfs</a></li></ul>";
                // display menu
               // alert(document.getElementById(ids+"ddcontent").innerHTML);
               
             // 将ddcontent显示 
              var c = document.getElementById(ids + 'ddcontent');
              c.style.display='block';
                
              var h = document.getElementById(ids + 'ddheader');
              c.style.left = (h.offsetWidth -1+ OFFSET) + 'px'; 
              c.style.height = 'auto';
                 
               // ddMenu(ids,1);
         
                //alert(document.getElementById(ids+"ddcontent").innerHTML );       
        }
    }
}