App\Http\Controllers\ImageController::utf8StringSplit PHP Method

    private function utf8StringSplit($string, $split_length = 1)
    {
        if (!preg_match('/^[0-9]+$/', $split_length) || $split_length < 1) {
            return false;
        }
        $len = mb_strlen($string, 'UTF-8');
        if ($len <= $split_length) {
            return array($string);
        }
        preg_match_all('/.{' . $split_length . '}|[^\\x00]{1,' . $split_length . '}$/us', $string, $ar);
        return $ar[0];
    }