Search for a key in a nested array

search_by_key_recursive.php

<?php 

function searchByKey(array $array, $key)
{
    if (array_key_exists($key, $array)) return $array[$key];

    $recursive = function($chunk) use ($key, &$recursive) {
        foreach ($chunk as $k => $v) {
            if ($k === $key) return $chunk[$key];
            if (is_array($v) && $found = $recursive($v)) return $found;
        }
        return null;
    };

    return $recursive($array);
}