array_key_last() │ WP 5.9.0

Get the last key of the given array without affecting the internal array pointer.

No Hooks.

Return

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

Usage

array_key_last( $arr );
$arr(array) (required)
An array.

Changelog

Since 5.9.0 Introduced.

Code of array_key_last() WP 6.0

wp-includes/compat.php 
function array_key_last( array $arr ) {
	if ( empty( $arr ) ) {
		return null;
	}
	end( $arr );
	return key( $arr );
}