Unable to add namespace to an attribute with PHP's SimpleXML

Question

I am creating an Atom feed, when I tried below to add xmlns:i as an attribute -

$node->addAttribute(\"xmlns:i\",\"http://www.w3.org/2001/XML         


        

Answer 1

If you want to add an attribute from the namespace/prefix i to $node don't bother declaring the namespace beforehand. Just use the third parameter of addAttribute() to provide the namespace uri for the prefix you're using in the first parameter.

$node = new SimpleXMLElement('');
$node->addAttribute("i:somename", "somevalue", 'http://www.w3.org/2001/XMLSchema-instance'); 
echo $node->asXml();

prints

If the attribute itself isn't needed, you can then remove it with unset(), leaving the namespace declaration.

unset($node->attributes('i', TRUE)['somename']);