我真的不知道這是否是關(guān)于SwiftMailer或mailtrap.io但問題是當(dāng)我嘗試建立到所述服務(wù)的 SMTP 連接時 ( mailtrap.io) 我從來沒有收到任何錯誤，即使我不使用任何用戶名或密碼。不使用任何用戶名或密碼時，我不應(yīng)該收到任何身份驗證錯誤嗎？還是我這樣做是錯誤的？這是我在將其存儲到.env文件中之前用于測試是否可以建立動態(tài)連接的方法。/** * E-mail configuration * * @param Request $request * @return \Illuminate\Routing\Redirector|\Illuminate\Http\RedirectResponse */public function postEmailConfiguration(Request $request){    # Try connecting to the SMTP    try {        $encryption = $request->input('encryption');        if ($encryption == 'null') {            $encryption = NULL;        }        $transport = new Swift_SmtpTransport($request->input('host'), $request->input('port'), $encryption);        $transport->setUsername($request->input('username'));        $transport->setPassword($request->input('password'));        $mailer = new Swift_Mailer($transport);        $mailer->getTransport()->start();        # Update .env file        $this->setEnvironmentValues([            'MAIL_HOST' => $request->input('host'),            'MAIL_PORT' => $request->input('port'),            'MAIL_USERNAME' => $request->input('username'),            'MAIL_PASSWORD' => $request->input('password'),            'MAIL_ENCRYPTION' => $request->input('encryption')        ]);        return redirect()->back()->with('success', 'Connection to SMTP establised and saved!');    }    # Could not connect to SMTP    catch (Swift_TransportException $e) {        return redirect()->back()->with('error', 'Could not connect to SMTP server.<br>Error: ' . $e->getMessage());    }    # Could not connect to SMTP    catch (Exception $e) {        return redirect()->back()->with('error', 'Could not connect to SMTP server.<br>Error: ' . $e->getMessage());    }}