public function sendResult($result)
    {
        if (@ob_get_length()) {
            @ob_end_clean();
        }
        if (isset($_SERVER['HTTP_ACCEPT']) && strpos($_SERVER['HTTP_ACCEPT'], 'application/json') !== false) {
            header('Content-Type: application/json; charset=' . APP_CHARSET, true);
        } else {
            header('Content-Type: text/plain; charset=' . APP_CHARSET, true);
        }
        echo json_encode($result);
        die();
    }