/*
		this function sends an ajax request to a specified url 
		
		strUrl: relative or abosulute page url
		query_string: posted parameters to url (formatted as get parameters)
		oncomplete: javascript function to be executed when Ajax request finishes
*/


function Ajax(strURL, query_string, onComplete) 
{
    var xmlHttpReq = false;
    var self = this;

    // Mozilla/Safari
    if (window.XMLHttpRequest) 
    {
        self.xmlHttpReq = new XMLHttpRequest();
    }
    // IE
    else if (window.ActiveXObject) 
    {
        self.xmlHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
    }
     
    self.xmlHttpReq.open('POST', strURL, true);
    self.xmlHttpReq.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    self.xmlHttpReq.onreadystatechange = function() 
    {
        if (self.xmlHttpReq.readyState == 4) 
        {
 				response = self.xmlHttpReq.responseText;
            
            onComplete(response);             
        }
    }
    
    self.xmlHttpReq.send(query_string);
    
    return self.xmlHttpReq;
}