function getXmlHttpRequest()
{
	var httpRequest = null;
	try
	{
		httpRequest = new ActiveXObject("Msxml2.XMLHTTP");
	}
	catch (e)
	{
		try
		{
			httpRequest = new ActiveXObject("Microsoft.XMLHTTP");
		}
		catch (e)
		{
			httpRequest = null;
		}
	}
	
	if (!httpRequest && typeof XMLHttpRequest != "undefined")
	{
		httpRequest = new XMLHttpRequest();
	}
	
	return httpRequest;
}

function getUrlSync(url)
{
	return getUrl(url, false, null);
}

function getUrlAsync(url, handleStateChange)
{
//	alert("Called");
	return getUrl(url, true, handleStateChange);
}


// call a url
function getUrl(url, async, handleStateChange) {
	var xmlHttpReq = getXmlHttpRequest();
   // alert("XMLHTTP Created.");
	if (!xmlHttpReq)
		return;

	if (handleStateChange)
	{
		xmlHttpReq.onreadystatechange = function()
			{
				handleStateChange(xmlHttpReq);
			};
	}
	else
	{
		xmlHttpReq.onreadystatechange = function() {;}
	}

	xmlHttpReq.open("GET", url, async);
	xmlHttpReq.send(null);
}

function postUrl(url, data, async, stateChangeCallback)
{ 
	var xmlHttpReq = getXmlHttpRequest(); 

	if (!xmlHttpReq)
		return;

	xmlHttpReq.open("POST", url, async);
	xmlHttpReq.onreadystatechange = function()
		{
			stateChangeCallback(xmlHttpReq);
		};
	xmlHttpReq.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
	xmlHttpReq.send(data);
	//alert ('url: ' + url + '\ndata: ' + data);
}

function execOnSuccess(stateChangeCallback)
{
	return function(xmlHttpReq)
		{
			if (xmlHttpReq.readyState == 4 &&
					xmlHttpReq.status == 200)
				stateChangeCallback(xmlHttpReq);
		};
}