在隐藏的C＃控制台应用程序中获取关闭窗口消息

Question

I have a Windows Form that starts some console application in background(CreateNoWindow = rue,WindowStyle = ProcessWindowStyle.Hidden).

Windows form gives me opportunity to stop the console application at any time. But I'd like to handle somehow the close message inside the console application. I tried to use hooking like:

    [DllImport("Kernel32")]
    public static extern bool SetConsoleCtrlHandler(HandlerRoutine handler, bool add);

    // A delegate type to be used as the handler routine 
    // for SetConsoleCtrlHandler.
    public delegate bool HandlerRoutine(CtrlTypes ctrlType);

    // An enumerated type for the control messages
    // sent to the handler routine.
    public enum CtrlTypes
    {
        CTRL_C_EVENT = 0,
        CTRL_BREAK_EVENT,
        CTRL_CLOSE_EVENT,
        CTRL_LOGOFF_EVENT = 5,
        CTRL_SHUTDOWN_EVENT
    }

    private static bool ConsoleCtrlCheck(CtrlTypes ctrlType)
    {
        StaticLogger.Instance.DebugFormat("Main: ConsoleCtrlCheck: Got event {0}.", ctrlType);
        if (ctrlType == CtrlTypes.CTRL_CLOSE_EVENT)
        {
            // Handle close stuff
        }
        return true;
    }

    static int Main(string[] args)
    {
        // Subscribing
        HandlerRoutine hr = new HandlerRoutine(ConsoleCtrlCheck);
        SetConsoleCtrlHandler(hr, true);
        // Doing stuff
    }

but I get the message inside ConsoleCtrlCheck only if the console window is created. But if window is hidden - I don't get any message.

In my windows Form to close console application process I use proc.CloseMainWindow(); to send message to the console window.

PS AppDomain.CurrentDomain.ProcessExit += CurrentDomain_ProcessExit; - also does not help

Do you now other way to handle this situation? Thanks.

Answer 1

This might work. I used it in NUnit testes to clean up environment. Unfortunately it is not garantieed to be called. To make it working you need to create an instance of it and pass callback function that should be called on shutdown.

    /// <summary>
    /// Detects the moment when environment is about to be shutdown.
    /// <remarks>
    ///     For usage just create single instance of it.
    ///     Each time when GC calles Finilize a '~ShutdownDetector' will be called.
    /// </remarks>
    /// </summary>
    public sealed class ShutdownDetector
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="T:ShutdownDetector"/> class.
        /// </summary>
        /// <param name="notifier">The notifier</param>
        public ShutdownDetector(Notifier notifier)
        {
            if (notifier == null) throw new ArgumentNullException("notifier");
            _notifier = notifier;
        }

        /// <summary>
        /// Releases unmanaged resources and performs other cleanup operations before the
        /// <see cref="T:CQG.PDTools.Common.ShutdownDetector"/> is reclaimed by garbage collection.
        /// </summary>
        ~ShutdownDetector()
        {
            if (Environment.HasShutdownStarted)
            {
                onShutdown();
            }
            else
            {
                new ShutdownDetector(_notifier);
            }
        }

        /// <summary>
        /// Called when component needs to signal about shutdown.
        /// </summary>
        private void onShutdown()
        {
            if (_notifier != null)
            {
                _notifier();
            }
        }

        Notifier _notifier;
        public delegate void Notifier();
    }