In a new tutorial on O'Reilly's ONLamp.com website today, Bill Lubanovic shows an example of moving a normal web-based PHP application over to a more Ajax-enabled environment.
In the web environment, we've typically needed hacks like populating hidden fields in a form, and regenerating the whole page, even for a tiny change. Can we make the process more rational?
In their example, they show how to take a simple form element, a select box of names, and modify it to work with an Ajax connection. Instead of having to submit the information back to to the PHP script with a form submit button, they can make a request when the user changes the select option to get that person's information. They've included all of the relevant code and some great explanation to help you recreate the example and move on to work up your own.