PHP数组,递归地将数组项的深度附加到具有"深度"键的数组

function addDepthToArray($array, $depth = 0) {
    $result = array();
    foreach ($array as $key => $value) {
        if (is_array($value)) {
            $result[$key] = addDepthToArray($value, $depth + 1);
        } else {
            $result[$key] = $value;
        }
    }
    $result['depth'] = $depth;
    return $result;
}

$array = array(
    'a' => 'value1',
    'b' => array(
        'c' => 'value2',
        'd' => array(
            'e' => 'value3'
        )
    ),
    'f' => 'value4'
);

$result = addDepthToArray($array);

print_r($result);

Array
(
    [a] => value1
    [b] => Array
        (
            [c] => value2
            [d] => Array
                (
                    [e] => value3
                    [depth] => 3
                )
            [depth] => 2
        )
    [f] => value4
    [depth] => 1
)