//ajax.js

function createRequest()
{
  var request = null;
  	try
  	{	
    	request = new XMLHttpRequest();
	}
	catch(trymicrosoft)
	{
	  	try
	  	{
		    request = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch(othermicrosoft)
		{
		  	try
		  	{
			    request = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch(failed)
			{
			  	request = null;
			}//catch Microsoft.XMLHTTP
		}//catch Msxml2.XMLHTTP
	}//catch XMLHTTPrEQUEST
	
	if(request == null)
	{
	  	alert("Error: cannot request object");
	}
	else
	{
	  	return request;
	}
}//createRequest

function sendGETRequest(request, url, callbackfunc,async)
{
  	request.open("GET", url, async);
  	request.onreadystatechange  = callbackfunc;
  	request.send(null);
}//sendGETRequest

function sendPOSTRequest(request, url, callbackfunc, contenttype, postData,async)
{
  	request.open("POST", url, async);
  	if (callbackfunc != null)
		request.onreadystatechange  = callbackfunc;
  	request.setRequestHeader("Content-type", contenttype);
  	request.send(postData);
  	
}