javascript:xmlhttprequest [JPSPAN]

XMLHttpRequest Introduction

XMLHttpRequest is a native JavaScript object allowing further HTTP requests to be made from a page which has already loaded. It allows Microrequests to be made in response to user events in a web page, rather than requiring a complete page reload, making it possible to implement some notion of a rich client user interface, similar to desktop applications.

The API provided allows a fairly fine grained level of control over HTTP requests, allowing any request header to be set and exposes all response headers.

The original implementation came from Microsoft as an ActiveX object for IE. Mozilla followed suit and implemented XMLHttpRequest with an (almost) identical API. Konqueror (and Safari v1.2, based also on KHTML) also has an XMLHttpRequest implementation and support should be coming in Opera from v7.6x .

This resource isn’t meant as a tutorial for XMLHttpRequest but rather to gather as much information about it as possible. See the Tutorials below for getting started.