The DOMXPath::registerNamespace() function is an inbuilt function in PHP which is used to register the namespaceURI and prefix with the DOMXPath object.
Syntax:
bool DOMXPath::registerNamespace( string $prefix,
string $namespaceURI )
Parameters: This function accepts two parameters as mentioned above and described below:
- $prefix: It specifies the prefix.
- $namespaceURI: It specifies the namespace URI.
Return Value: This function returns TRUE on success or FALSE on failure.
Below given programs illustrate the DOMXPath::registerNamespace() function in PHP:
Program 1:
<?php   // Create a new DOMDocument instance $document = new DOMDocument();   // Create a XML $xml = <<<XML <?xml version="1.0" encoding="UTF-8"?> <body xmlns="neveropen" >     <h1>Hello</h1> </body> XML;   // Load the XML $document->loadXML($xml);   // Create a new DOMXPath instance $xpath = new DOMXPath($document);   // Register namespace with prefix // x and wrong URI $xpath->registerNamespace('x',               'neveropennew');   // Use the prefix to create a query // to get the text in h1 $query = '//x:body/x:h1/text()';   // Execute the query $entries = $xpath->evaluate($query);   // Count the output echo count($entries) . "\n"; ?> |
Output:
0
Program 2:
<?php   // Create a new DOMDocument instance $document = new DOMDocument();   // Create a XML $xml = <<<XML <?xml version="1.0" encoding="UTF-8"?> <body xmlns="neveropen" >     <h1>Hello</h1> </body> XML;   // Load the XML $document->loadXML($xml);   // Create a new DOMXPath instance $xpath = new DOMXPath($document);   // Register namespace with prefix x $xpath->registerNamespace('x',                'neveropen');   // Use the prefix to create a query // to get the text in h1 $query = '//x:body/x:h1/text()';   // Execute the query $entries = $xpath->evaluate($query);   // View the text echo $entries->item(0)->nodeValue . "\n"; ?> |
Output:
Hello
Reference: https://www.php.net/manual/en/domxpath.registernamespace.php
