javascript解析返回的xml各式的字符串

<script>
var flags ;
  if(window.XMLHttpRequest) { 
   XMLHttpReq = new XMLHttpRequest(); //firefox下执行此语句
   }
   else if(window.ActiveXObject) {
    try{
    XMLHttpReq = new ActiveXObject("Msxm12.XMLHTTP");
    }catch(e){
     try{
     XMLHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
     }catch(e) {}
    }
   }
   XMLHttpReq.open("post","getDate.jsp",false);
   XMLHttpReq.setRequestHeader("CONTENT-TYPE","application/x-www-form-urlencoded;charset=UTF-8");
   XMLHttpReq.onreadystatechange = function () {
   var statePending = XMLHttpReq.readyState;
   if (statePending == 4&& XMLHttpReq.status==200)
   {
    if(window.ActiveXObject){
     xmlDoc = new ActiveXObject('Microsoft.XMLDOM');
     xmlDoc.async = false;
     xmlDoc.loadXML(XMLHttpReq.responseText.replace(/(^\s*)/g, ""));
    } else if (document.implementation&&document.implementation.createDocument){
     XMLHttpReq.open("GET",XMLHttpReq.responseText.replace(/(^\s*)/g, ""),false);
     XMLHttpReq.send(null);
     xmlDoc = XMLHttpReq.responseXML;
     //return new XMLSerializer().serializeToString(xmlDoc);
    }
    flags = xmlDoc.getElementsByTagName("content");
   }
   }
   XMLHttpReq.send(null);
   for(var i =0;i<flags.length;i++)
   {
   var content = flags[i]; //得一个content结