public function CheckUserLogOn ( $username, $password ) {
        if ($stmt = $mysqli->prepare("SELECT username, password FROM fish WHERE username=$username password=$password") ) {
            $stmt->bind_result($username, $password);

            try {
                $stmt->execut();
            } catch (Exception $e) {
                echo $e->getTraceAsString();
            }




             $stmt->close();
        }