var xmlhttp

function showGiftBox(str)
{
xmlhttp=GetXmlHttpObject();
if (xmlhttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  }
var url="getgiftbox.asp";
url=url+"?str="+str;
xmlhttp.onreadystatechange=stateChanged2;
xmlhttp.open("GET",url,true);
xmlhttp.send(null);
}

function stateChanged2()
{
if (xmlhttp.readyState==4)
  {
  document.getElementById("txtHint1").innerHTML=xmlhttp.responseText;
  document.getElementById('chkDup').disabled = true; 
  }
}

function GetXmlHttpObject2()
{
if (window.XMLHttpRequest)
  {
  // code for IE7+, Firefox, Chrome, Opera, Safari
  return new XMLHttpRequest();
  }
if (window.ActiveXObject)
  {
  // code for IE6, IE5
  return new ActiveXObject("Microsoft.XMLHTTP");
  }
return null;
}