c# - 创建新线程时，不对 GUI 进行更改 (C#)

Question

在一些帮助下，我设法创建了一个新线程，尽管该方法似乎在执行，但该方法的条件要么使绿灯亮起，要么使红灯亮起，尽管在没有新线程的情况下运行该方法(Check1..etc)线程更改会反射(reflect)在 GUI 上(例如出现红灯/绿灯)，但是当创建新线程并运行该方法时，更改不会反射(reflect)在表单/GUI 上。

// Method / Action to start the checks         private void StartChecks_Click(object sender, EventArgs e)
        {

            Thread t = new Thread(
               o =>
               {
                   InitChecks();
               });
            t.Start();
        }

// Check1 public void Check1()
        {

            // lets grabs the info from the config!
            var lines = File.ReadAllLines("probe_settings.ini");
            var dictionary = lines.Zip(lines.Skip(1), (a, b) => new { Key = a, Value = b })
                                  .Where(l => l.Key.StartsWith("#"))
                                  .ToDictionary(l => l.Key, l => l.Value);

            // lets set the appropriate value for this check field
            label1.Text = dictionary["#CheckName1"];

            // lets define variables and convert the string in the dictionary to int for the sock.connection method!

            int portno1;
            int.TryParse(dictionary["#PortNo1"], out portno1);

            // Convert hostname to IP, performance issue when using an invalid port on a hostname using the TcpClient class! 
            IPAddress[] addresslist = Dns.GetHostAddresses(hostname2);

            foreach (IPAddress theaddress in addresslist)
            {
                // Attempt to create socket and connect to specified port on host
                TcpClient tcP = new System.Net.Sockets.TcpClient();
                try
                {
                    tcP.ReceiveTimeout = 1;
                    tcP.SendTimeout = 1;
                    tcP.Connect(theaddress, portno1);
                    displayGreen1();
                    tcP.Close();
                }
                catch
                {
                    displayRed1();
                }
            }

        }

// Change the lights when the condition is met

        public void displayGreen1()
        {
            pictureBox2.Visible = false;
            pictureBox1.Visible = true;
        }

        private void displayRed1()
        {
            pictureBox2.Visible = true;
            pictureBox1.Visible = false;
        }

Answer 1

这就是 WinForms 的设计方式。您不能从另一个线程进行更改。 解决方案通常是使用异步委托(delegate)。

首先添加这个声明

 public delegate void MyDelegate1 ();

 public delegate void MyDelegate2 (); 

然后当你在另一个线程中时你应该这样做:

MyDelegate1 d1= new MyDelegate1 (displayGreen1);

 this.BeginInvoke(d1);

 MyDelegate2 d2= new MyDelegate2 (displayRed1);

 this.BeginInvoke(d2);