var xmlHttpdropdown

function chekdropdown(strdropdown)
{
//alert("hello");

if (strdropdown.length==0)
  { 
  document.getElementById("txtHintdropdown").innerHTML="";
  return;
  }
xmlHttpdropdown=GetXmlHttpObjectdropdown();
if (xmlHttpdropdown==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  } 
var urldropdown="checkdropdown.php";
urldropdown=urldropdown+"?q="+strdropdown;
urldropdown=urldropdown+"&sid="+Math.random();
xmlHttpdropdown.onreadystatechange=stateChangeddropdown;
xmlHttpdropdown.open("GET",urldropdown,true);
xmlHttpdropdown.send(null);
} 

function stateChangeddropdown() 
{ 

if (xmlHttpdropdown.readyState==4)
{ 
//document.getElementById("txtHint").innerHTML=xmlHttp.responseText;
if (xmlHttpdropdown.status==200) {
            // we use a delay only for this example
            setTimeout('loadResultsdropdown()',100);
        }
}
}

function GetXmlHttpObjectdropdown()
{
	
var xmlHttpdropdown=null;
try
  {
  // Firefox, Opera 8.0+, Safari
  xmlHttpdropdown=new XMLHttpRequest();
  }
catch (e)
  {
  // Internet Explorer
  try
    {
    xmlHttpdropdown=new ActiveXObject("Msxml2.XMLHTTP");
    }
  catch (e)
    {
    xmlHttpdropdown=new ActiveXObject("Microsoft.XMLHTTP");
    }
  }
return xmlHttpdropdown;
} 
 function loadResultsdropdown() {
	
	  document.getElementById("txtHintdropdown").innerHTML=xmlHttpdropdown.responseText;
	 document.getElementById('txtHintdropdown').innerHTML = '<img id="submitImage" name="submitImage" src="http://examsheets.net/images/loading.gif" alt="AJAX Results Ready">';
	 
	 setTimeout('resetImagedropdown()',2000);
    
}
function resetImagedropdown() {
	document.getElementById("txtHintdropdown").innerHTML=xmlHttpdropdown.responseText;
}