The DOMNode::lookupPrefix() function is an inbuilt function in PHP which is used to get the namespace prefix of the node based on the namespace URI.
Syntax:
string DOMNode::lookupPrefix( string $namespaceURI )
Parameters: This function accepts a single parameter $namespaceURI which holds the namespace URI.
Return Value: This function returns the prefix of the namespace.
Below examples illustrate the DOMNode::lookupPrefix() function in PHP:
Example 1:
php
<?php // Create a new DOMDocument instance $document = new DOMDocument(); // Load the XML with no namespace $document ->loadXML("<?xml version=\"1.0\"?> <div > <h1> neveropen </h1> </div> "); // Get the prefix with namespace URI "my_namespace" $prefix = $document ->documentElement-> lookupPrefix( "my_nsamespace" ); echo $prefix ; ?> |
Output:
// Empty string as there is no such namespace
Example 2:
php
<?php // Create a new DOMDocument instance $document = new DOMDocument(); // Load the XML with a namespace with prefix x $document ->loadXML("<?xml version=\"1.0\"?> <div xmlns:x=\"my_namespace\"> <x:h1 x:style=\"color:red;\"> neveropen </x:h1> </div> "); // Get the prefix with namespace URI "my_namespace" $prefix = $document ->documentElement-> lookupPrefix( 'my_namespace' ); echo $prefix ; ?> |
Output:
x
Reference: https://www.php.net/manual/en/domnode.lookupprefix.php