PHP Manual: SimpleXMLElement::key

Description

public function SimpleXMLElement::key(): string

Warning

Prior to PHP 8.0, SimpleXMLElement::key() was only declared on the subclass SimpleXMLIterator.

This method gets the XML tag name of the current element.

Parameters

This function has no parameters.

Return Values

Returns the XML tag name of the element referenced by the current SimpleXMLElement object.

Errors/Exceptions

Throws an Error on failure.

Changelog

Version	Description
8.1.0	An Error is now thrown if SimpleXMLElement::key() is called on an invalid iterator. Previously, `false` was returned.

Examples

Example #1 Get the current XML tag key

<?php
$xmlElement = new SimpleXMLElement('<books><book>PHP basics</book><book>XML basics</book></books>');

try {
    echo var_dump($xmlElement->key());
} catch (Error $e) {
    echo $e->getMessage(), "\n";
}

$xmlElement->rewind(); // rewind to the first element
echo var_dump($xmlElement->key());

?>

The above example will output:

Iterator not initialized or already consumed
string(4) "book"