//**********************************************************************************
//NEW AJAX OBJECT ORIENTED APPROUCH (HANDLES PARALLEL REQUESTS)

function AJAXRequest(url, callback) {

    var req = init();
    req.onreadystatechange = processRequest;
        
    function init() {    
      if (window.XMLHttpRequest) {        
        return new XMLHttpRequest();
      } else if (window.ActiveXObject) {        
        return new ActiveXObject("Microsoft.XMLHTTP");
      }
      return null;
    }
    
    function processRequest () {
          if (callback) callback(req);
    }

    this.doGet = function() {            
      req.open("GET", url, true);
      req.send(null);
    }
    
    this.doPost = function(body) {
      req.open("POST", url, true);
      req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
      req.send(body);
    }
}
//**********************************************************************************