public static function mbStringPad($input, $pad_length, $pad_string = ' ', $pad_type = STR_PAD_RIGHT, $encoding = NULL)
    {
        if (!$encoding)
        {
            $diff = strlen($input) - mb_strlen($input);
        }
        else
        {
            $diff = strlen($input) - mb_strlen($input, $encoding);
        }

        return str_pad($input, $pad_length + $diff, $pad_string, $pad_type);
    }