function GetXmlHttpObject() {
   var xmlHttp=null;
   try
     {
     // Firefox, Opera 8.0+, Safari
     xmlHttp=new XMLHttpRequest();
     }
   catch (e)
     {
     // Internet Explorer
     try
       {
       xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
       }
     catch (e)
       {
       xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
       }
     }
   return xmlHttp;
}

function stateChanged() {
   if (xmlHttp.readyState==4) {
      var response = xmlHttp.responseText;
   }
}