August 2012
Beginner
583 pages
16h 1m
English
Content preview from Learning PHP, MySQL, JavaScript, and CSS, 2nd EditionBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Sending XML Requests
Although the objects we’ve been creating are called XMLHttpRequest objects, so far we have made
absolutely no use of XML. This is where the term “Ajax” is a bit of a
misnomer, because the technology actually allows you to request any type
of textual data, with XML being just one option. As you have seen, we have
requested an entire HTML document via Ajax, but we could equally have
asked for a text page, a string or number, or even spreadsheet
data.
So, let’s modify the previous example document and PHP program to fetch some XML data. To do this, take a look at the PHP program first: xmlget.php, shown in Example 17-6.
Example 17-6. xmlget.php
<?php
if (isset($_GET['url'])) {
header('Content-Type: text/xml');
echo file_get_contents("http://".sanitizeString($_GET['url']));
}
function sanitizeString($var) {
$var = strip_tags($var);
$var = htmlentities($var);
return stripslashes($var);
}
?>This program has been very slightly modified (the changes are shown in bold) to first output the correct XML header before returning a fetched document. No checking is done here, as it is assumed the calling Ajax will request an actual XML document.
Now on to the HTML document, xmlget.html, shown in Example 17-7.
Example 17-7. xmlget.html
<html><head><title>Ajax XML Example</title>
</head><body>
<h2>Loading XML content into a DIV</h2>
<div id='info'>This sentence will be replaced</div>
<script>
nocache = "&nocache=" + Math.random() * 1000000
url = "rss.news.yahoo.com/rss/topstories" ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.