var xmlHttp

function showHint(str)
{
if (str.length==0)
  { 
  document.getElementById("txtHint").innerHTML="";
  return;
  }
xmlHttp=GetXmlHttpObject();
if (xmlHttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  }        
var url="sub_category_lookup.php";
url=url+"?id="+str;
url=url+"&sid="+Math.random();
xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET",url,true);
xmlHttp.send(null);
} 

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

function GetXmlHttpObject()
{
var xmlHttp=null
if (window.XMLHttpRequest)
{
xmlHttp=new XMLHttpRequest()
}
else if (window.ActiveXObject)
{
xmlHttp=new ActiveXObject("Microsoft.XMLHTTP")
}
return xmlHttp
}