var xmlHttp

function showCD(str)
{ 
xmlHttp=GetXmlHttpObject()
if (xmlHttp==null)
 {
 alert ("Browser does not support HTTP Request")
 return
 } 
var url="ajax.php"
url=url+"?q="+str
url=url+"&sid="+Math.random()
xmlHttp.onreadystatechange=stateChanged 
xmlHttp.open("GET",url,true)
xmlHttp.send(null)
}

function stateChanged() 
{ 
 if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
 { 
 document.getElementById("txtHint").innerHTML=xmlHttp.responseText 
 } 
}

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;
}



// Error: uncaught exception: Permission denied to call method XMLHttpRequest.open

  var http_request = false;

  function makeRequest(url, parameters) {

   try {
    netscape.security.PrivilegeManager.enablePrivilege("UniversalBrowserRead");
   } catch (e) {
    alert("Permission UniversalBrowserRead denied.");
   }

    http_request = false;
    http_request = new XMLHttpRequest();
    if (http_request.overrideMimeType) {
      http_request.overrideMimeType('text/xml');
    }
    if (!http_request) {
      alert('Cannot create XMLHTTP instance');
      return false;
    }
    http_request.onreadystatechange = alertContents;
    http_request.open('GET', url + parameters, true);
    http_request.send(null);
  }

  function alertContents() {
    if (http_request.readyState == 4) {
      if (http_request.status == 200) {

        var string = http_request.responseText;
      alert(string);

      } else {
        alert('There was a problem with the request.');
      }
    }
  }
  function updateweather() {
    makeRequest('http://www.wunderground.com/auto/rss_full/global/stations/16239.xml', '');
  }