var http_request;

function getHttpObject()
{
    var object = false;
    
    if(window.XMLHttpRequest)
    {
        object = new XMLHttpRequest();
    }
    else if(window.ActiveXObject)
    {
        try
        {
            object = new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch(e)
        {
            try
            {
                object = new ActiveXObject("Microsoft.XMLHTTP");
            }
            catch(e)
            {
            }
        }
    }
    
    return object;
}

function ajax_GetRequest(url, handler)
{
    http_request = getHttpObject();
    
    if(http_request)
    {
        http_request.onreadystatechange = handler;
        http_request.open("GET", url, true);
        http_request.send("");
    }
}

function ajax_PostRequest(url, handler, data)
{
    http_request = getHttpObject();
    
    if(http_request)
    {
        http_request.onreadystatechange = handler;
        http_request.open("POST", url, true);
        http_request.setRequestHeader("Content-Type", "application/x-www-urlencoded");
        http_request.setRequestHeader("Content-Length", data.length);
        http_request.setRequestHeader("Connection", "close");
        http_request.send(data);
    }
}


function sample_ajax_Handler()
{
    if(http_request.readyState == 4)
    {
        if(http_request.status == 200)
        {
            var text = http_request.responseText;
            //var xml = http_request.responseXML;
            
            // do something with text (or xml).
        }
    }
}