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371

xml versus json

Chapter 1: Boards ‘R’ Us

Chapter 2: Break Neck Pizza

Chapter 3: Ajax Coffee Maker

Chapter 5: Break Neck Revisited

Chapter 4: Top 5 CDs

Chapter 6: Boards ‘R’ Us (expanded)

PHP script

<?php

require(‘lib.php’);

function go() {

$myVar = ...

return ...

}

?>

PHP script

<?php

require(‘lib.php’);

function go() {

$myVar = ...

return ...

}

?>

PHP script

<?php

require(‘lib.php’);

function go() {

$myVar = ...

return ...

}

?>

Plain Text

Requests

Plain Text

Responses

Plain Text

Request

XML Response

Everything in the rst part of the

book sent text to the server using

name/value pairs.

All these earlier apps got text

back from the server, too.

Remember, even with POST

requests in Chapter 5, we

were sending plain text.

Chapter 4 was all about

the DOM... no requests or

responses here.

In Chapter 6, we were still

sending text in our requests.

The server nally got to say

more, though, and sent XML

back in its responses.

A review of request and response formats

Before we dive into the JSON versus XML debate, let’s review the data

formats we’ve already used in the rst six chapters.

XML makes it easy

for the server to

send more complex

responses to your

requests... but your

requests are still

usually better off

as plain text.