PHP: DOMDocument - attributes with a colon in it?

Question

I'm using DOMDocument to parse an XML (SVG).

Some nodes have attributes with a colon in it, like :

<svg 
   id="svg2"
   width="1000"
   height="1000"
   sodipodi:version="0.32"
   inkscape:version="0.48.1 "
   ...
>

But when I do :

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

the attributes with a : are printed without the first part (namespace)

How do I get the namespace for that attribute when iterating through the attributes like this?

Answer 1

Answer from OP's comment, nodeName from DOMNode.

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

Original Answer:

How about prefix from DOMNode?

$node= DOMDocument->documentElement;
foreach($node->childNodes as $key=>$childnode) {
  foreach($childnode->attributes as $attribute) {
    echo $attribute->prefix.":".$attribute->name."\n";
  }
}