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phpsimplexmlxml-namespaces

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

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/XMLSchema-instance");

I got this as an output -

i="http://www.w3.org/2001/XMLSchema-instance"

"xmlns:" part was cut off. do I need to escape the :-character? Or is they any other way to add this namespace?

Solution

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

    prints

    <?xml version="1.0"?>
<root xmlns:i="http://www.w3.org/2001/XMLSchema-instance" i:somename="somevalue"/>

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

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