It creates a namespace context for the next XPath query

Example

<?php
$xml = simplexml_load_file(“test.xml”);
$xml->registerXPathNamespace(“msg”,”http://www.phpcodez.com”);
$result = $xml->xpath(“msg:web”);
?>

XML

<?xml version=”1.0″ encoding=”ISO-8859-1″?>
<web>
<server ver=”5″>Apache</server>
<lan>PHP</lan>
<client>Javascript</client>
</web>