PHP | SimpleXMLElement getDocNamespaces() Function

Pre-requisite: Read XML Basics

The SimpleXMLElement::getDocNamespaces() function is an inbuilt function in PHP which is used to retrieve the namespaces declared in XML document.

Syntax:

array SimpleXMLElement::getDocNamespaces( $recursive, $from_root )

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

• $recursive: It is optional and boolean parameter. Its default value is False. If True is passed as parameter then it returns namespaces in parent as well as child node recursively. If it set to False then it only returns the namespaces of the parent node.
• $from_root: It is optional and boolean parameter. The default value is True. If it set to True then it will check namespaces from the root of the XML document. If it set to False then it will check namespaces under a child node.

Return Value: This function returns an array of namespace names with their associated URIs.

Note: This function is available for PHP 5.1.2 and newer version.

Below programs illustrate the SimpleXMLElement::getDocNamespaces() function in PHP:

Program 1:

<?php

// Loading XML document to $user
$user = <<<XML
<user xmlns:user_id="http://geeksforgeeks.org/user">
<single_user id="1">
    <user_id:id>12345</user_id:id>
    <username>Geeks123</username>
    <name>GeeksforGeeks</name>
    <phone>+91-XXXXXXXXXX</phone>
    <detail font-color="blue" font-size="24px">
        Noida India
    </detail>
</single_user>

<single_user id="2">
    <user_id:id>15980</user_id:id>
    <username>Geeks54321</username>
    <name>Geeks</name>
    <phone>+91-XXXXXXXXXX</phone>
    <detail font-color="blue" font-size="24px">
        Noida India
    </detail>
</single_user>
</user>
XML;

// Loading string as simple xml object
$xml = simplexml_load_string($user);

// Retrieving namespaces
$result = $xml->getDocNamespaces();

// Display output
print_r($result);

?>

Output:

Array
(
    [user_id] => http://geeksforgeeks.org/user
)

Program 2:

<?php

// Loading XML document to $user
$user = <<<XML
<user xmlns:user_id="http://geeksforgeeks.org/user">
    <single_user id="1" xmlns:name="http://geeksforgeeks.org/user/name">
        <user_id:id>12345</user_id:id>
        <username>rakesh123</username>
        <name:firstname>Rakesh</name:firstname>
        <name:lastname>Kumar</name:lastname>
        <phone>+91-XXXXXXXXXX</phone>
        <detail>Noida India</detail>
    </single_user>

    <single_user id="2" xmlns:name="http://geeksforgeeks.org/user/name">
        <user_id:id>57833</user_id:id>
        <username>man123</username>
        <name:firstname>Manjeet</name:firstname>
        <name:lastname>Singh</name:lastname>
        <phone>+91-XXXXXXXXXX</phone>
        <detail>Kolkata, India</detail>
    </single_user>

    <single_user id="3" xmlns:name="http://geeksforgeeks.org/user/name">
        <user_id:id>98944</user_id:id>
        <username>ak98</username>
        <name:firstname>Ak</name:firstname>
        <name:lastname>Singh</name:lastname>
        <phone>+91-XXXXXXXXXX</phone>
        <detail>Noida India</detail>
    </single_user>
</user>
XML;

// Loading string as simple xml object
$xml = simplexml_load_string($user);

// Retrieving namespaces
$result = $xml->getDocNamespaces(TRUE);

// Displaying output
print_r($result);

?>

Output:

Array
(
    [user_id] => http://geeksforgeeks.org/user
    [name] => http://geeksforgeeks.org/user/name
)

Reference:https://www.php.net/manual/en/simplexmlelement.getdocnamespaces.php