There doesn't seem to be a way to entirely remove an attribute

[jackwh]

If you write an attribute to a node, it's only possible to empty it out, but the attribute tag will always remain on the node.

There should be some kind of removeAttribute function I think - DOMElement has this built-in.

[jackwh]

Whoops, sorry! I'm wrong. It wasn't in the docs, but I discovered it was possible like so:

$this->xml->query("//MyDocument/MyElements/Element[@AttributeToRemove]")->each(function ($index, $domElement) {
    $domElement->removeAttribute('AttributeToRemove');
});

[daniele-orlando]

Yes, perfect solution. That's exactly the way to remove an attribute.

Fluidxml doesn't re-implement what DOM performs quite well.