// JavaScript Document

var xmlHttp
function CheckFile(a)
{ 
	var username = a;
//	alert(username);
	if(EmailValidation(username)==false)
	{
		alert('Enter Valid Mail Id');
		document.getElementById('user_mailid').focus();
	}


xmlHttp=GetXmlHttpObject();
if (xmlHttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  } 
var url="check_user.php";
url=url+"?username="+username;
url=url+"&sid="+Math.random();
xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET",url,true);
xmlHttp.send(null);
}
function stateChanged() 
{ 
	if (xmlHttp.readyState==4)
	{ 
		document.getElementById("error_msg").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;
}
function EmailValidation(str)
{
	var apos = str.indexOf("@");
	var dotpos = str.lastIndexOf(".");
	if(apos<1 || dotpos-apos <2)
	{
		return false;
	}
	else
	{
		return true;
	}
}