递归数组键替换

Question

I have quite big recursive array with mixed numeric and string keys.

Which is the fastest way to replace the numeric keys with string keys (prefix each numeric with item_)?

eg.

array('key_1' => 'val1', 2 => array( 3 => 'val3'));

to

array('key_1' => 'val1', 'item_2' => array('item_3' => 'val3'));

I want the order of the items remain the same.

Answer 1

function replace_numeric_keys(&$array) {
    $result = array();
    foreach ($array as $key => $value) {
        if (is_int($key)) $key = "item_$key";
        if (is_array($value)) $value = replace_numeric_keys($value);
        $result[$key] = $value;
    }
    return $result;
}