The term Ajax has come to represent a broad group of web technologies that can be used to implement a web application that communicates with a server in the background, without interfering with the current state of the page. Mr. Jesse James Garrett explained that the following technologies are required.
- HTML or XHTML and CSS for presentation.
- DOM for dynamic display of and interaction with data.
- XML and XSLT for the interchange, and manipulation and display, of data, respectively.
- XMLHttpRequest object for asynchronous communication.
Ajaxs most appealing characteristic, however, is its asynchronous nature, which means it can do all of this without having to refresh the page. This allows you to update portions of a page based upon user. The DOM plays into Ajax in a number of ways. How you use the DOM depends a good deal on how you handle the content returned from the server. You can show the content as simple text using the responseText property of the server response, or you can get it as XML using responseXML. Assuming the content you pull back from the server is an (X)HTML snippet and youve gotten it as responseText, you could drop/print that content into a particular spot on the page using innerHTML(May be in a div or a table).
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