Tracking namespace declarations with XMLWriter

Question

Hi,

I'm working on an XML webservice (in PHP!), and in order to do things 'right', I want to use XMLWriter instead of just concatinating strings and hoping for the best.

I'm using XML namespaces everywhere using ->startElementNS and ->writeElementNS. The problem, is that every time I use these functions a new namespace declaration is also writting.

While this is correct syntax, it's a bit unneeded. I'd like to make sure my namespace declaration is only written the first time it's used in the context of a document.

Is there an easy way to go about this with XMLWriter, or am I stuck subclassing this and managing this manually.

Thanks, Evert

Answer 1

You can pass NULL as the uri parameter.

<?php
$w = new XMLWriter;
$w->openMemory();
$w->setIndent(true);
$w->startElementNS('foo', 'bar', 'http://whatever/foo');
$w->startElementNS('foo', 'baz', null);
$w->endElement();
$w->endElement();
echo $w->outputMemory();

prints

<foo:bar xmlns:foo="http://whatever/foo"&gt;
 <foo:baz/>
</foo:bar>