PHP | DOMElement getElementsByTagNameNS() Function

Last Updated : 05 Mar, 2020

The DOMElement::getElementsByTagNameNS() function is an inbuilt function in PHP which is used to get all the descendant elements with a given localName and namespaceURI. Syntax:

DOMNodeList DOMElement::getElementsByTagNameNS( 
          string $namespaceURI, string $localName )

Parameters: This function accept two parameters as mentioned above and described below:

$namespaceURI: It specifies the namespace URI.
$localName: It specifies the local name.

Return Value: This function returns a DOMNodeList value containing all matched elements in the order in which they are encountered in a preorder traversal of this element tree. Below given programs illustrate the DOMElement::getElementsByTagNameNS() function in PHP: Program 1:

php

<?php
// Create a new DOMDocument
$dom = new DOMDocument();
 
// Load the XML
$dom->loadXML("<?xml version=\"1.0\"?>
<root>
    <div xmlns:x=\"my_namespace\">
        <x:h1 x:style=\"color:red;\">
            Hello, this is my red heading.
        </x:h1>
        <x:h1 x:style=\"color:green;\">
            Hello, this is my green heading.
        </x:h1>
        <x:h1 x:style=\"color:blue;\">
            Hello, this is my blue heading.
        </x:h1>
    </div>
    <div xmlns:y=\"another_namespace\">
        <y:h1 y:style=\"color:red;\">
            Hello, this is my new red heading.
        </y:h1>
        <y:h1 y:style=\"color:green;\">
            Hello, this is my new green heading.
        </y:h1>
        <y:h1 y:style=\"color:blue;\">
            Hello, this is my new blue heading.
        </y:h1>
    </div>
</root>");
 
// Get the elements with h1 tag from
// specific namespace
$nodeList = $dom->getElementsByTagNameNS(
                    'my_namespace', 'h1');

foreach ($nodeList as $node) {
    echo $node->getAttribute('x:style') . '<br>';
}
?>

Output:

color:red;
color:green;
color:blue;

Program 2:

php

<?php

// Create a new DOMDocument
$dom = new DOMDocument();
 
// Load the XML
$dom->loadXML("<?xml version=\"1.0\"?>
<root>
    <div xmlns:x=\"my_namespace\">
        <x:p>HELLO.</x:p>
        <x:p>NEW.</x:p>
        <x:p>WORLD.</x:p>
    </div>
    <div xmlns:y=\"g4g_namespace\">
        <y:p>GEEKS</y:p>
        <y:p>FOR</y:p>
        <y:p>GEEKS</y:p>
    </div>
</root>");
 
// Get the elements
$nodeList = $dom->getElementsByTagNameNS(
                    'g4g_namespace', 'p');

foreach ($nodeList as $node) {
    echo $node->textContent . '<br>';
}
?>