DOMDocument xmlns attributes - how to get them?

I'm using DOMDocument to read an XML (SVG), which has namespac开发者_StackOverflowes in it. I iterate through the attributes of all nodes, but I can't seem to get the 'xmlns' type attributes of the root element.

The XML looks like this :

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<svg
   xmlns:dc="http://purl.org/dc/elements/1.1/"
   xmlns:cc="http://creativecommons.org/ns#"
   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
   xmlns:svg="http://www.w3.org/2000/svg"
   xmlns="http://www.w3.org/2000/svg"
   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"

   id="svg2"
   sodipodi:version="0.32"
   inkscape:version="0.48.1 "
   viewBox="0,0 534,616"

   ...
>

When I try something lke this :

$node= DOMDocument->documentElement;
foreach($node->attributes as $attribute) {
  echo $attribute->nodeName."\n";
}

I do get the 'other' attributes like id, viewBox, etc. but not the xlmns:dc, etc.

Is there a way to get those too ?

Try with namespaceURI

The namespace URI of this node, or NULL if it is unspecified.

To get the default namespaceURI of the root node, you use

$dom->documentElement->namespaceURI;

demo

See my answer in the linked duplicate on how to get all the namespace attributes.

An alternative to that would be using XPath:

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

demo

If you are parsing through the document, extracting the namespace prefixes from each attribute value and then using DOMNode::lookupNamespaceURI ( string $prefix ) to build the prefix-uri mappings will result in less overhead than using simplexml.