AJAX

  javascript 中

  var count;
  var oXML=new ActiveXObject("Microsoft.XMLDOM");
  oXML.async=false;
  var url="调用servlet";
  oXML.load(url);
                alert(oXML.documentElement);
   var currNode = oXML.documentElement.selectSingleNode("Count");
  if(currNode==null){
   window.alert ("Data format error!");
   window.alert (oXML.xml);
   return null;
  }
  else{
   count= currNode.text;
  }
  if(count=="0"){
   if((pNotFoundMessage+""!="undefined")&&(pNotFoundMessage!="")&&(pNotFoundMessage!=null)){
    alert (pNotFoundMessage);
    return null;
   }
          else{
           alert( "Code not exist!");
           return null;
          }
  }
         var currNode = oXML.documentElement;

     下面可以从xml文件中获取数据，更新html页面。