PHP: retrieve all declared namespaces of a DOMElement

Question

I am using the DOM extension to parse an xml file containing xml namespaces. I would have thought that namespace declarations are treated just like any other attribute, but

Answer 1

Unless there is a more direct way you can use XPath and its namespace axis.
e.g.

loadxml('
...
');
$context = $doc->documentElement;

$xpath = new DOMXPath($doc);
foreach( $xpath->query('namespace::*', $context) as $node ) {
  echo $node->nodeValue, "\n";
}

prints

http://www.w3.org/XML/1998/namespace
http://webns.net/mvcb/
http://purl.org/rss/1.0/modules/prism/
http://purl.org/rss/1.0/modules/syndication/
http://purl.org/dc/elements/1.1/
http://purl.org/rss/1.0/modules/taxonomy/
http://purl.org/rss/1.0/
http://www.w3.org/1999/02/22-rdf-syntax-ns#

---

edit and btw: I haven't found documentation for DOMNameSpaceNode either. But you can "deduct" (parts of) its functionality from the source code in ext/dom/php_dom.c
It doesn't seem to expose any methods and exposes the properties

"nodeName", "nodeValue", "nodeType",
"prefix", "localName", "namespaceURI",
"ownerDocument", "parentNode"

all handled by the same functions as the corresponding DOMNode properties.