php error when XML item does not exist - php

Question

I am using PHP to grab an XML feed and display it in my website, the feed is coming from
This NewsReach Blog.
I am using some simple PHP code to get the details as show below:
$feed = new SimpleXMLElement('http://blog.newsreach.co.uk/atom.xml', null, true);
$i = 0;
foreach($feed->entry as $entry)
{
if ($i < 4)
{
$title = mysql_real_escape_string("{$entry->title}");
$summary = mysql_real_escape_string("{$entry->content}");
$summary = strip_tags($summary);
$summary = preg_replace('/\s+?(\S+)?$/', '', substr($summary, 0, 100));
$url = mysql_real_escape_string("{$entry->link[4]['href']}");
$media = $entry->children('http://search.yahoo.com/mrss/');
$attrs = $media->thumbnail[0]->attributes();
$img = $attrs['url'];
}
}
The problem that I have is that the media thumbnail tag does not exist in every blog post which causes an error to appear and stop the XML Grabber from functioning.
I have tired things like:
if ($media == 0)
{
}
else
{
$attrs = $media->thumbnail[0]->attributes();
$img = $attrs['url'];
}
or
if ($media['thumbnail'] == 0)
{
}
else
{
$attrs = $media->thumbnail[0]->attributes();
$img = $attrs['url'];
}
which I had no luck with, I was hoping someone could help me check if the XML Item existed and then process depending on that.
Thanks all

Answer 1

You could check if it's set and not empty:
$img = '';
if (!empty($media->thumbnail[0])) {
$attrs = $media->thumbnail[0]->attributes();
$img = $attrs['url'];
}
Remember that $media is an object, you can't access it like an array ($media['thumbnail'] should be $media->thumbnail).