array_key_last()WP 5.9.0

Gets the last key of the given array. Does not touch the internal pointer of the array.

The function does not care what type of array was passed (indexed or associative), it will return the last key (index) of the specified array in any case.

This is a polyfill for the function array_key_last(), added in PHP 7.3.

Use array_key_first() when you need to get the first key of the array.

1 time — 0.000003 sec (speed of light) | 50000 times — 0.0001 sec (speed of light)

No Hooks.

Returns

String|Int|null. The last key of the array, if the array is not empty; null otherwise.

Usage

array_key_last( $arr );
$arr(array) (required)
The array whose last key needs to be obtained.

Examples

0

#1 Demo

$key = array_key_last( [ 1, 2 ] ); // 1

$key = array_key_last( [ 'one' => 1, 'two' => 2 ] ); // two
0

#2 Not affect the internal array pointer

An example of how the internal array pointer is stored.

$arr = [
	'one' => 1,
	'two' => 2
];
reset( $arr ); // switch the internal array pointer

echo key( $arr ); // one

echo array_key_last( $arr ); // two

echo key( $arr ); // one

Changelog

Since 5.9.0 Introduced.

array_key_last() code WP 6.9

function array_key_last( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
	if ( empty( $array ) ) {
		return null;
	}

	end( $array );

	return key( $array );
}