Create a dynamic XML href in PHP with SimpleXML - php

Question

I'm trying to create a link based on a URL variable using only the last five digits of its respective line of XML data.
For example, if the XML link is http://events.stanford.edu/events/213/21389 how can I create this link a href="e/?i=21389?
Here's my page, XML and code:
<?php
// Build the XML file path, using URL variable $c (above)
$c = $_GET['c'];
$p ="http://events-prod.stanford.edu/xml/byCategory/";
$e = "/mobile.xml";
$file = "$p$c$e";
$xml = simplexml_load_file($file);
?>
<h1><?php echo $xml->title; ?></h1>
Home
</div><!-- /header -->
<div data-role="content">
<?php // Only display if there are events ?>
<?php if (isset($xml->Event->title)) { ?>
<ul data-role="listview">
<?php foreach($xml->Event as $event) { ?>
<li>
<a href="<?php echo $event->link; ?>">
<?php if ($event->Media->url != null) { ?>
<img src="<?php echo $event->Media->url;?>" alt="<?php echo $event->title;?> thumbnail" />
<?php } ?>
<h3><?php echo $event->title; ?></h3>
<p><strong><?php echo $event->beginDate; ?> at <?php echo $event->beginTime; ?></strong></p>
<p><?php echo $event->locationText; ?></p>
</a>
</li>
<?php } ?>
</ul>
<?php } else { ?>
<?php echo '<p>There is currently nothing scheduled for ', $xml->title, '.</p>';?>
<?php } ?>

Answer 1

I'm using short tags, because I think you'll agree it's easier now to read the code as oppose to before.
<?
$controller ="http://events-prod.stanford.edu/xml/byCategory/";
$category_id = $_GET['c'];
$category_id = 0;
$xml = "/mobile.xml";
$url = $controller . $category_id . $xml;
$xml_object = simplexml_load_file($url);
?>
<div>
<h1><?= $xml_object->title ?></h1>
Home
</div>
<div data-role="content">
<? if (!empty($xml_object->Event->title)): ?>
<ul data-role="listview">
<? foreach($xml_object->Event as $event): ?>
<li>
<?
$pattern = '/[0-9]+$/';
$matches = array();
preg_match($pattern, $event->link, $matches);
$my_link = 'e/?i=' . $matches[0];
?>
<a href="<?= $my_link ?>">
<? if (!empty($event->Media->url)): ?>
<img src="<?= $event->Media->url ?>" alt="<?= $event->title ?> thumbnail" />
<? endif; ?>
<h3><?= $event->title ?></h3>
<p><strong><?= $event->beginDate ?> at <?= $event->beginTime ?></strong></p>
<p><?= $event->locationText ?></p>
</a>
</li>
<? endforeach; ?>
</ul>
<? else: ?>
<? echo '<p>There is currently nothing scheduled for ', $xml_object->title, '.</p>'; ?>
<? endif; ?>
</div>