var frm;
function checkUsername(frmObj, uname, pagename, mode)
{	
	var PostParam = "";
	frm = frmObj;

	PostParam = "vUsername="+uname+'&pagename='+pagename+'&mode='+mode;
	var url = site_url+"username_verification.php?";
	var contentType = "application/x-www-form-urlencoded; charset=UTF-8";
	var params = PostParam;
  	url = url+PostParam;
	//alert(url);return false;
	if (window.XMLHttpRequest) 
	{
        http = new XMLHttpRequest();
        http.onreadystatechange = handleHttpResponse_status;
		http.open("post", url, true);
        http.setRequestHeader("Content-Type", contentType);
        http.send(params);
        status = true;
		// ActiveX XMLHttpRequest object
    }
	else if (window.ActiveXObject) 
	{
        http = new ActiveXObject("Microsoft.XMLHTTP");
        if (http) 
		{
            http.onreadystatechange = handleHttpResponse_status;
            http.open("post", url, true);
            http.setRequestHeader("Content-Type", contentType);
			http.send(params);
            status = true;
        }
    }
}

function handleHttpResponse_status() 
{ 
	if (http.readyState == 4) 
	{	
      	isWorking = false;
    	if (http.responseText.indexOf('invalid') == -1) 
		{
    		var xmlDocument = http.responseXML; 
			var objIdvar = xmlDocument.getElementsByTagName('exist').item(0).firstChild.data;
			if(objIdvar == '-1')
			{
				alert("Invalid Site Access...!!!");
				window.location(site_url);
				return false;
			}
			else if(objIdvar == '2')
			{
				alert("Username can't be blank... Please Try again.");
				return false;
			}
			else if(objIdvar == '1')
			{
				alert("Username Already Exists... Please Try again.");
				return false;
			}
			else
			{
				frm.submit();
			}
		}
	}	
}