var xmlHttp;

function initAjax(url,post,handle)
{
	xmlHttp=GetXmlHttpObject();
	if (xmlHttp==null)
		{
		alert ("Browser does not support HTTP Request");
		return;
		}
	xmlHttp.onreadystatechange=function() {stateChanged(handle)};
	xmlHttp.open("POST",url,true);
	xmlHttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded;charset=ISO-8859-2'); 
	xmlHttp.send(post);
}

function stateChanged(handle)
{
	if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
		{
			switch (handle)
			{
			case 'checkUsername':
				{
				if (xmlHttp.responseText.indexOf("div")>-1)
					{
					document.getElementById('logon').innerHTML=xmlHttp.responseText;
					}
				else
					{
					alert(xmlHttp.responseText);
					}
				break;
				}
			}
		}
}

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