c# - C＃属性値を変更してスレッドからアクティビティを変更することはできません

Question

at コマンドで SMS を送信するアプリケーションを作成しましたが、問題があります。COM7 と COM8 に 3 つの gsm モデムが接続されています。

私のコードは正常に動作しますが、SMS 送信が「エラー」になっている場合、現在のポート (例: COM7) を COM8 にソフト変更する必要があります...

私のコード:

public clsWorker(SMSapplication app, SerialPort serialPort, SerialPort serialPort2, String urlChamp)
        {
            // Récupération du port principal
            this.port = serialPort;

            // Récupération du nom des ports
            this.port_name1 = serialPort.PortName;

            if (serialPort2.PortName == "" || serialPort2.PortName == null)
                this.port_name2 = serialPort.PortName;
            else
                this.port_name2 = serialPort2.PortName;

            // Récupération de l'url de check
            this.url = urlChamp;

            // Récupération de l'instance de la fenetre
            this.clsobjAPP = app;

            // On initialise le contenu du label avec le port actuel
            clsobjAPP.updateCurrentPort(this.port.PortName);

            //MessageBox.Show("Changement de port: " + this.port_name1 + " et " + this.port_name2);
        }


        public void StartThread()
        {
            t = new Thread(new ThreadStart(ThreadLoop));
            //clsobjSMS.setPinCode(this.port, "1234");
            t.Start();
        }


        // I want to change the port name is they is an error
        public void ChangePort()
        {

            if (this.port.PortName == this.port_name1)
            {
                // This don't work... Do you know why ??
                this.port.PortName = this.port_name2;
                MessageBox.Show("Change the current port to: " + this.port.PortName);
                clsobjAPP.updateCurrentPort("coucou1");
            }
            else if (this.port.PortName == this.port_name2)
            {
                // This don't work... Do you know why ??
                this.port.PortName = this.port_name1;
                MessageBox.Show("Change the current port to: " + this.port.PortName);
                clsobjAPP.updateCurrentPort("coucou2");
            }
            else
            {
                clsobjAPP.updateCurrentPort("erreur");
                MessageBox.Show("Erreur !");
            }

        }


        public void ThreadTimer()
        {

            t = new Thread(new ThreadStart(ThreadTimer));
            compareDate = DateTime.Now.AddMinutes(2);
            systemDate = DateTime.Now;

            while(true)
            {


                if (this.compareDate < DateTime.Now)
                {
                    this.StopThread();
                    this.systemDate = DateTime.Now;
                    this.compareDate = DateTime.Now.AddMinutes(2);
                    //MessageBox.Show("Launche every 2 minutes");

                }
                else
                {
                    if (!t.IsAlive)
                    {
                        this.StartThread();

                    }

                }
            }


        }



        public void ThreadLoop()
        {

            while (Thread.CurrentThread.IsAlive)
            {

                // Initialisation des variables:
                string destinataire_mobile = "";
                string destinataire_message = "";
                string id = "";
                string sms_envoye_le = "";
                string hash_envoi = "";
                string expediteur_ip = "";
                string lcHtml = "";


                Thread.Sleep(10000);


                try
                {


                    string lcUrl = this.url;
                   // "http://texto-sms-gratuit.com/android/etat_sms.php?etat=nok";
                    // *** Establish the request
                    HttpWebRequest loHttp = (HttpWebRequest)WebRequest.Create(lcUrl);

                    // *** Set properties
                    loHttp.Timeout = 6000;     // 10 secs
                    loHttp.UserAgent = "Serveur Texto-SMS-Gratuit.Com";

                    // *** Retrieve request info headers
                    HttpWebResponse loWebResponse = (HttpWebResponse)loHttp.GetResponse();

                    Encoding enc = Encoding.GetEncoding(1252);  // Windows default Code Page

                    StreamReader loResponseStream = new StreamReader(loWebResponse.GetResponseStream(), enc);


                    lcHtml = loResponseStream.ReadToEnd();


                    if (lcHtml == "null" || lcHtml.Length < 10 || lcHtml == "")
                        continue;

                    if (lcHtml == "<meta http-equiv=\"Refresh\" content=\"0\">")
                        continue;

                    JArray ja = JArray.Parse(lcHtml);


                    // Data extract of Json
                    id = ja[0]["id"].ToString();

                    // Mise en attente du msg
                    WebClient myWebClient = new WebClient();
                    myWebClient.DownloadString("http://site.com");

                    destinataire_mobile = ja[0]["destinataire_mobile"].ToString();
                    destinataire_message = ja[0]["destinataire_message"].ToString();
                    sms_envoye_le = ja[0]["sms_envoye_le"].ToString();
                    hash_envoi = ja[0]["hash_envoi"].ToString();
                    expediteur_ip = ja[0]["expediteur_ip"].ToString();


                    loWebResponse.Close();
                    loResponseStream.Close();

                    if (destinataire_mobile != "" && destinataire_message != "" && id != "")
                    {
                        if (destinataire_message.Length >= 159)
                            destinataire_message = destinataire_message.Substring(0, 159);

                        if (destinataire_mobile.Length >= 159)
                            destinataire_mobile = destinataire_mobile.Substring(0, 12);


                        if (destinataire_mobile[3].ToString() == "6" || destinataire_mobile[3].ToString() == "7")
                        {
                            if (clsobjSMS.sendMsg(this.port, destinataire_mobile, destinataire_message))
                            {
                                // Message sent
                                myWebClient.DownloadString("http://site.com/");
                                clsobjAPP.updateCountSMS("countSMSok");
                            }
                            else
                            {
                               // Message sent ERROR !!
                                myWebClient.DownloadString("http://site.com");
                                clsobjAPP.updateCountSMS("countSMSnok");


                                // This method don't work, and I don't know why ...?
                                this.ChangePort();



                            }
                        }
                    }

                }
                catch (Exception ex)
                {
                    //(ex.Message);

                }


            }
        }
    }

大変お世話になりました。よろしくお願いします、