// Script 13.2 - ajax.js

 /* This page creates an Ajax request
object.
 * This page is included by other pages
that
 * need to perform an XMLHttpRequest.
 */

 // Initialize the object:
 var ajax = false;

 // Create the object...

 // Choose object type based upon what's supported:
 if (window.XMLHttpRequest) {

 // IE 7, Mozilla, Safari, Firefox,Opera, most browsers:
 ajax = new XMLHttpRequest();

 } else if (window.ActiveXObject) { //Older IE browsers

 // Create type Msxml2.XMLHTTP, if possible:
 try {
 ajax = new
ActiveXObject("Msxml2.XMLHTTP");
 } catch (e1) { // Create the older type instead:
 try {
 ajax = new
ActiveXObject("Microsoft.XMLHTTP");
 } catch (e2) { }
 }

 }

 // Send an alert if the object wasn't created.
 if (!ajax) {
 alert ("Your browser does not support AJAX!");
 }