xajax PHP Class Library
Ajax-enable your PHP application with a simple toolkit that gets the job done fast:
xajax is an open source PHP class library that allows you to easily create powerful, web-based, Ajax applications using HTML, CSS, JavaScript, and PHP. Applications developed with xajax can asynchronously call server-side PHP functions and update content without reloading the page.
The xajax PHP object generates JavaScript wrapper functions for the PHP functions you want to be able to call asynchronously from your application. When called, these wrapper functions use JavaScript’s XMLHttpRequest object to asynchronously communicate with the xajax object on the server which calls the corresponding PHP functions. Upon completion, an xajax XML response is returned from the PHP functions, which xajax passes back to the application. The XML response contains instructions and data that are parsed by xajax’s JavaScript message pump and used to update the content of your application.
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Check these out –
http://developer.yahoo.net/ypatterns/
http://developer.yahoo.net/yui/