我希望能够在c#控制台应用程序中捕获Ctrl+C,以便在退出之前执行一些清理。做这件事最好的方法是什么?


当前回答

检测SIGTERM和Ctrl+C:

CancellationTokenSource ctSource = new();
CancellationToken ct = ctSource.Token;

void ExitHandler()
{
    // You can add any arbitrary global clean up
    Console.WriteLine("Exiting...");
    ctSource.Cancel();
}

// Assign exit handler to be called when the process is terminated
// or the user hits CTRL+C
AppDomain.CurrentDomain.ProcessExit += (sender, args) => ExitHandler();
Console.CancelKeyPress += (sender, args) => ExitHandler();

// Then you can use the cancellation token to check for exit:
Console.WriteLine("Ready to gracefully shut down!");
while (!ct.IsCancellationRequested)
{
    Console.WriteLine($"Exit not detected, waiting another 10s.");
    Task.Delay(10000, ct).Wait(ct);
}

其他回答

下面是一个完整的工作示例。粘贴到空的c#控制台项目:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;

namespace TestTrapCtrlC {
    public class Program {
        static bool exitSystem = false;

        #region Trap application termination
        [DllImport("Kernel32")]
        private static extern bool SetConsoleCtrlHandler(EventHandler handler, bool add);

        private delegate bool EventHandler(CtrlType sig);
        static EventHandler _handler;

        enum CtrlType {
            CTRL_C_EVENT = 0,
            CTRL_BREAK_EVENT = 1,
            CTRL_CLOSE_EVENT = 2,
            CTRL_LOGOFF_EVENT = 5,
            CTRL_SHUTDOWN_EVENT = 6
        }

        private static bool Handler(CtrlType sig) {
            Console.WriteLine("Exiting system due to external CTRL-C, or process kill, or shutdown");

            //do your cleanup here
            Thread.Sleep(5000); //simulate some cleanup delay

            Console.WriteLine("Cleanup complete");

            //allow main to run off
            exitSystem = true;

            //shutdown right away so there are no lingering threads
            Environment.Exit(-1);

            return true;
        }
        #endregion

        static void Main(string[] args) {
            // Some biolerplate to react to close window event, CTRL-C, kill, etc
            _handler += new EventHandler(Handler);
            SetConsoleCtrlHandler(_handler, true);

            //start your multi threaded program here
            Program p = new Program();
            p.Start();

            //hold the console so it doesn’t run off the end
            while (!exitSystem) {
                Thread.Sleep(500);
            }
        }

        public void Start() {
            // start a thread and start doing some processing
            Console.WriteLine("Thread started, processing..");
        }
    }
}

我想补充一下乔纳斯的回答。在bool上旋转将导致100%的CPU利用率,并且在等待CTRL+C时浪费大量的能量。

更好的解决方案是使用ManualResetEvent来实际“等待”CTRL+C:

static void Main(string[] args) {
    var exitEvent = new ManualResetEvent(false);

    Console.CancelKeyPress += (sender, eventArgs) => {
                                  eventArgs.Cancel = true;
                                  exitEvent.Set();
                              };

    var server = new MyServer();     // example
    server.Run();

    exitEvent.WaitOne();
    server.Stop();
}

我可以在离开前做一些清理工作。做这件事最好的方法是什么 这才是真正的目标:走出陷阱,做你自己的东西。以上两个答案都不是正确的。因为Ctrl+C只是退出应用程序的众多方法之一。

在dotnet c#中需要什么-所谓的取消令牌传递给Host.RunAsync(ct),然后,在退出信号陷阱中,对于Windows它将是

    private static readonly CancellationTokenSource cts = new CancellationTokenSource();
    public static int Main(string[] args)
    {
        // For gracefull shutdown, trap unload event
        AppDomain.CurrentDomain.ProcessExit += (sender, e) =>
        {
            cts.Cancel();
            exitEvent.Wait();
        };

        Console.CancelKeyPress += (sender, e) =>
        {
            cts.Cancel();
            exitEvent.Wait();
        };

        host.RunAsync(cts);
        Console.WriteLine("Shutting down");
        exitEvent.Set();
        return 0;
     }

...

控制台。TreatControlCAsInput = true;对我很有效。

检测SIGTERM和Ctrl+C:

CancellationTokenSource ctSource = new();
CancellationToken ct = ctSource.Token;

void ExitHandler()
{
    // You can add any arbitrary global clean up
    Console.WriteLine("Exiting...");
    ctSource.Cancel();
}

// Assign exit handler to be called when the process is terminated
// or the user hits CTRL+C
AppDomain.CurrentDomain.ProcessExit += (sender, args) => ExitHandler();
Console.CancelKeyPress += (sender, args) => ExitHandler();

// Then you can use the cancellation token to check for exit:
Console.WriteLine("Ready to gracefully shut down!");
while (!ct.IsCancellationRequested)
{
    Console.WriteLine($"Exit not detected, waiting another 10s.");
    Task.Delay(10000, ct).Wait(ct);
}