C# 在程序的另一个实例上显示窗体

我编写了一个程序，它使用ApplicationContext在窗体关闭时继续运行。通过单击托盘图标可以再次显示表单，但我希望它在应用程序再次运行时也显示其表单，而不是运行另一个程序实例

我已经尝试实施问题中建议的解决方案，但我似乎无法让PostMessage发挥作用。我已经成功地实现了命名管道，但是在获取等待消息与ApplicationContext通信的线程时遇到了问题

我知道我见过其他具有此功能的应用程序，所以我的问题是：这通常是如何实现的？我找到的所有解决方案似乎都适用于其他人，所以我肯定错过了一些简单的东西

编辑： 抱歉没有包括一个例子。我解决了这个问题，在设置之前我使用了

SynchronizationContext.Current

。我通过在构建表单之后而不是之前构建MessageReceiver类来修复它。这是我的代码，以防有人发现它有用

在

程序

类中：

    private const byte Activate = 3 << 3;

    [STAThread]
    private static void Main()
        {
        using (var mtx =
            new Mutex(true, "{F6878DF0-C021-4B4F-934A-7FB03957E09F}",
                      out var createdNew))
            {
            if (createdNew)
                {
                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);
                Application.Run(new AppContext(Activate));
                }
            else
                {
                //if the program is already running, make a NamedPipeServer
                //and wait for it to connect, then write the Activate message
                using (var pipeServer =
                    new NamedPipeServerStream("testpipe",
                                              PipeDirection.Out))
                    {
                    pipeServer.WaitForConnection();
                    pipeServer.WriteByte(Activate);
                    }
                }
            }
        }

private class MessageReceiver
    {
        public event EventHandler MessageReceived;
        private readonly SynchronizationContext _sync;
        private Thread _waitThread;
        private readonly byte _activate;

        public MessageReceiver(byte activateMessage)
            {
            _sync = SynchronizationContext.Current;
            _activate = activateMessage;
            }

        public void StopWait()
            {
            _waitThread.Abort();
            }

        private void WaitInternal()
            {
            while (true)
                {
                using (var client = new NamedPipeClientStream(
                    ".", "testpipe", PipeDirection.In))
                    {
                    //block until we can connect to the pipe server
                    client.Connect();
                    //read a byte from the stream and check if it's
                    //the activate signal
                    if (client.ReadByte() != _activate) continue;
                    //if so, invoke the MessageRecieved event on the
                    //thread that created the MessageReceiver
                    _sync.Send(
                        state =>
                            MessageReceived?.Invoke(
                                this, EventArgs.Empty), null);
                    }
                }
            }

        public void BeginWait()
            {
            if (_waitThread.ThreadState == ThreadState.Running
             || _waitThread.ThreadState == ThreadState.AbortRequested)
                return;
            _waitThread = new Thread(WaitInternal);
            _waitThread.Start();
            }
    }

MessageReceiver

类：

    private const byte Activate = 3 << 3;

    [STAThread]
    private static void Main()
        {
        using (var mtx =
            new Mutex(true, "{F6878DF0-C021-4B4F-934A-7FB03957E09F}",
                      out var createdNew))
            {
            if (createdNew)
                {
                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);
                Application.Run(new AppContext(Activate));
                }
            else
                {
                //if the program is already running, make a NamedPipeServer
                //and wait for it to connect, then write the Activate message
                using (var pipeServer =
                    new NamedPipeServerStream("testpipe",
                                              PipeDirection.Out))
                    {
                    pipeServer.WaitForConnection();
                    pipeServer.WriteByte(Activate);
                    }
                }
            }
        }

private class MessageReceiver
    {
        public event EventHandler MessageReceived;
        private readonly SynchronizationContext _sync;
        private Thread _waitThread;
        private readonly byte _activate;

        public MessageReceiver(byte activateMessage)
            {
            _sync = SynchronizationContext.Current;
            _activate = activateMessage;
            }

        public void StopWait()
            {
            _waitThread.Abort();
            }

        private void WaitInternal()
            {
            while (true)
                {
                using (var client = new NamedPipeClientStream(
                    ".", "testpipe", PipeDirection.In))
                    {
                    //block until we can connect to the pipe server
                    client.Connect();
                    //read a byte from the stream and check if it's
                    //the activate signal
                    if (client.ReadByte() != _activate) continue;
                    //if so, invoke the MessageRecieved event on the
                    //thread that created the MessageReceiver
                    _sync.Send(
                        state =>
                            MessageReceived?.Invoke(
                                this, EventArgs.Empty), null);
                    }
                }
            }

        public void BeginWait()
            {
            if (_waitThread.ThreadState == ThreadState.Running
             || _waitThread.ThreadState == ThreadState.AbortRequested)
                return;
            _waitThread = new Thread(WaitInternal);
            _waitThread.Start();
            }
    }

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请出示你的密码。我们需要一个命名管道，这是一个很好的方向。分享与该部分相关的代码以及您遇到问题的地方。有不同的可能性。使用互斥体、消息、命名管道、UI自动化或上述部分/全部的组合（也是互斥体+注册表项或RegisterWindowMessage+PostThreadMessage/PostMessage…）。您需要展示您正在做的事情，并解释在定义的情况下它在哪里失败或不能按预期工作。此代码重新发明了一个已经在.NET Framework中实现的功能。