// JavaScript Document
var xmlHttp

function checkUser(str){
	if (str.length==0){ 
	  document.getElementById("txtuser").innerHTML="";
	  return;
	}
	xmlHttp=GetXmlHttpObject()
	if (xmlHttp==null){
	  alert ("Your browser does not support AJAX!");
	  return;
	} 
	var url="usercheck.asp";
	url=url+"?user="+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("txtuser").innerHTML=xmlHttp.responseText;
	}
	}
	
function GetXmlHttpObject(){
	var xmlHttp=null;
	try{
	  xmlHttp=new XMLHttpRequest();
	}catch (e){
	  	try{
		xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
	 }catch (e){
		xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
	  }
	}
	return xmlHttp;
}