For PHP < 7.3.0 :
Will work for any type of array
<?php
if ( ! function_exists( 'array_key_last' ) ) {
/**
* Polyfill for array_key_last() function added in PHP 7.3.
*
* Get the last key of the given array without affecting
* the internal array pointer.
*
* @param array $array An array
*
* @return mixed The last key of array if the array is not empty; NULL otherwise.
*/
function array_key_last( $array ) {
$key = NULL;
if ( is_array( $array ) ) {
end( $array );
$key = key( $array );
}
return $key;
}
}
?>