public static function str_ireplace($search, $replace, $str, $count = null)
    {
        if (!function_exists('utf8_ireplace')) {
            require_once __DIR__ . '/phputf8/str_ireplace.php';
        }

        if ($count === null) {
            return utf8_ireplace($search, $replace, $str);
        }

        return utf8_ireplace($search, $replace, $str, $count);
    }