XMLHttpRequest object. When these technologies are combined in the Ajax model, Web applications are able to make quick, incremental updates to the user interface without reloading the entire browser page. The source code is available for all the scripts.
Simple Ajax by Jeff Manning
A simple script that simplifies Ajax requests
JSONplus by Josip Kalebic
One of the main problems with manipulating XML files is the compatibility issue across different browsers. The purpose of the SoftXMLLib Library is to solve the problem of creating different XMLHTTP and XMLDOM objects for different browsers. This library includes basic functions and properties like those already included in Microsoft.XMLDOM ActiveXObject.
When a visitor clicks on a specific link, the content of that link is inserted into the page without a refresh. When a page doesn't exist, a user-friendly error message is given. [Note: This is an edited version of the original script.]
Use this script instead of frames. When a visitor clicks on a specific link, the content of that link is inserted into the page without a refresh. When a page doesn't exist, a user-friendly error message is given.
Creating the XMLHTTPRequest Object
Many browsers allow the XMLHTTPRequest object to be created directly. One method is to use this snippet. It tries all methods of creating the object until it discovers one that works.
Check Username Signup
This script does a Gmail-style check on the username supplied to see if it is a unique username, using the Ajax method (via the Sajax development version).
Ajax Loader 2
Use this script to load XML and HTML files with XMLHTTPREQUEST. In the div id=EchoTopic tag, just add the name of the file to load and the element to display the file in, usually a div element.