//---- Ajax basics
//---- Created by Gon Perez-Jimenez with educational purposes in mind
//---- http://phpgon.com
//---- May 2009

  // Retrieve data using the XMLHttpRequest object
function ajax_call_server( url, vars )
{
 var xml = null;
 try
 {
    xml = new ActiveXObject("Microsoft.XMLHTTP");
 }
 catch(exception)
 {
    xml = new XMLHttpRequest();
 }

 if(xml!=null)
 {
    xml.open("GET",url + vars, false);
    xml.send(null);
    if(xml.status == 404) alert("Error 404: Incorrect url.");
    return xml.responseText;
 }
 alert("Your browser does not support XMLHTTP.");
 return "";
}

  // Call this function to load asynchronously any page into
  // the DIV you want with id=div_container_id passing all
  // GET parameters you want via "params" variable
function ajax_load_page( params,
                         div_container_id,
                         print_loading_message,
                         print_loading_icon )
{
 if(print_loading_icon)
 {
    document.getElementById(div_container_id).innerHTML = 
          '<center><img src="res/loading.gif" width="32" height="32"/></center>';
    setTimeout("ajax_load_page('"+params+"','"+div_container_id+"',false,false);",250);
 }
 else
 if(print_loading_message)
 {
    document.getElementById(div_container_id).innerHTML = 
          '<div class="ajax_loading_message">Loading...</div>';
    setTimeout("ajax_load_page('"+params+"','"+div_container_id+"',false,false);",250);
 }
 else
 {
    var response = ajax_call_server( "ajax-page-loader.php", "?"+params );
    document.getElementById(div_container_id).innerHTML = response;
 }
}