ajax中的responseXML

Question

  function callback() {
            if (xmlHttp.readyState == 4) {
                if (xmlHttp.status == 200) {
                  
                    var mes = xmlHttp.responseXML.getElementsByTagName("message")[0]; 
                    alert(mes);
                    var val = xmlHttp.responseXML.getElementsByTagName("passed")[0].Text;//
                    setMessage(mes, val);
                    alert("b");
                     
                }
            }
        }
页面请求返回：
 context.Response.Write("<?xml version=\"1.0\"?><response><passed>False</passed><message>You have entered an invalid date.</message></response>");问题：1、alert(mes) 为空？取不到值。
      2、目的：取出节点的值xmlHttp.responseXML.getElementsByTagName("passed")[0].Text; 语句有没有错？

Answer 1

 已经加了 context.Response.ContentType = "text/xml;charset=UTF-8";

Answer 2

还有把前台的html代码删掉只留下<%@page...

Answer 3

自己搞定了
  function callback() {
            if (xmlHttp.readyState == 4) {
                if (xmlHttp.status == 200) {
                  var requestMsg=xmlHttp.responseText;                 
                  var xmlDoc = new ActiveXObject("Msxml2.DOMDocument");                  
                  xmlDoc.loadXML(requestMsg);         
                  var mes = xmlDoc.getElementsByTagName("message")[0].Text; 
                   var val = xmlDoc.getElementsByTagName("passed")[0].Text;//
                    setMessage(mes, val);
                                     
                     
                }
            }
        }