DOMXPath::registerPhpFunctionNS

(PHP >= 8.4.0)

DOMXPath::registerPhpFunctionNSRegister a PHP functions as namespaced XPath function

Description

public DOMXPath::registerPhpFunctionNS(string $namespaceURI, string $name, callable $callable): void

This method enables the ability to use a PHP function as a namespaced XPath function inside XPath expressions.

Liste de paramètres

namespaceURI
The URI of the namespace.
name
The local function name inside the namespace.
callable
The PHP function to call when the XPath function gets called within the XPath expression. When a node list is passed as parameter to the callback, they are arrays containing the matched DOM nodes.

Valeurs de retour

Aucune valeur n'est retournée.

Exemples

Exemple #1 Register a namespaced XPath function and call it from the XPath expression

<?php
$xml
= <<<EOB
<books>
<book>
<title>PHP Basics</title>
<author>Jim Smith</author>
<author>Jane Smith</author>
</book>
<book>
<title>PHP Secrets</title>
<author>Jenny Smythe</author>
</book>
<book>
<title>XML basics</title>
<author>Joe Black</author>
</book>
</books>
EOB;

$doc = new DOMDocument;
$doc->loadXML($xml);

$xpath = new DOMXPath($doc);

// Register the my: namespace (required)
$xpath->registerNamespace("my", "urn:my.ns");

// Register PHP functions (no restrictions)
$xpath->registerPHPFunctionNS(
'urn:my.ns',
'substring',
fn (array
$arg1, int $start, int $length) => substr($arg1[0]->textContent, $start, $length)
);

// Call substr function on the book title
$nodes = $xpath->query('//book[my:substring(title, 0, 3) = "PHP"]');

echo
"Found {$nodes->length} books starting with 'PHP':\n";
foreach (
$nodes as $node) {
$title = $node->getElementsByTagName("title")->item(0)->nodeValue;
$author = $node->getElementsByTagName("author")->item(0)->nodeValue;
echo
"$title by $author\n";
}

?>

Résultat de l'exemple ci-dessus est similaire à :

Found 2 books starting with 'PHP':
PHP Basics by Jim Smith
PHP Secrets by Jenny Smythe

Voir aussi

add a note

User Contributed Notes

There are no user contributed notes for this page.
To Top