Problems with first_child() and child_nodes() in xmldom and php4

schorschi0351

Hi,

I just started using XML in php and want to use www.php.net/xmldom

But somehow it is not working like expected and I don't know why... Would be great if someone here can give me some hints:

I want to parse an RSS file:
(The url is in $url, the file is a valid xml file with all the child nodes, so the file is ok)

$xml=domxml_open_file($url);
$node=$xml->document_element();
echo $node->tagname();

so far this is working, the output is 'rss', everything fine. But now I want to move one level down:

$node2=$node->first_child();
echo $node2->tagname();

HERE IS THE PROBLEM: no output. $node2 is null! Why? The child node is 'channel', I can clearly see it in the source code!

Now I tried something else:

$titles=$xml->get_elements_by_tagname();
foreach ($titles as $title) {
echo $title->tagname();
}

is working, so it finds childs within the dom. why doesn't it find anything with first_child() ?

I also tried child_nodes():

$node2=$node->child_nodes();
foreach ($node2 as $node3) {
$node3->tagname();
}

also NOT working ("Fatal error: call to undefined function: tagname() ....") so child_nodes() gave null as result. Unbelievable! And I just got results from the very same file!

Would be great if someone knows about this and could help me.

Thanks,
Raik

bpat1434

The proper link is:

www.php.net/domxml

For all intents and purposes, the DOM XML in PHP is not the greatest. PHP 5 really superceded the previous DOM XML with it's DOM extension. If there is any way possible, upgrade to PHP 5.

As for your problem, I can't say why first_child() won't work. It should, but it's a "non-supported" and very loosely documented function. If there's any way you can work with elements_by_tagname to get what you want, I'd use that. Or upgrade to PHP 5 with the more-updated DOM.

~Brett