控制台检查按下的键，就像在单人游戏中一样

Question

在我的控制台应用程序中，我希望能够像mono一样检测按键，在mono中，您可以获得当前按键的列表，并检查列表中是否有按键，或者检测是否有按键被按下。我的使用问题

if( Console.KeyAvailable ) k = Console.ReadKey( true ).Key;

我按下第一个键后会有延迟。如果你打开记事本并按住“A”，你可以看到这样的例子。A将被按下，然后是延迟，然后A将被垃圾邮件发送。

我怎样才能得到键盘输入没有延迟之间的按下？我不怕使用低级功能，比如钩住kernel32.dll

Answer 1

所以我写了一些代码，基于我到目前为止读到的内容。

步骤1：将以下代码复制到控制台应用程序中。它必须是StatThread，否则将抛出错误。在switch语句中输入要使用的命令。所有其他键将被ReadKey阻止（true）。

using System.Diagnostics;
using System.Runtime.InteropServices;
using System.IO;
using System;
using System.Windows.Forms;
using System.Windows.Input;

namespace ConsoleApplication10
{
    class Program
    {
        [STAThread]
        static void Main(string[] args)
        {
            KeyListener.RegisterHotKey(Keys.A);
            KeyListener.HotKeyPressed += new EventHandler<HotKeyEventArgs>(KeyListener_HotKeyPressed);
            while (true)
            {
                Console.ReadKey(true);
            }
        }

        static void KeyListener_HotKeyPressed(object sender, HotKeyEventArgs e)
        {
            switch (e.Key)
            {
                case Keys.A:
                {
                    Console.WriteLine("Do stuff");
                    return;
                }
                default:
                    return;
            }
        }
    }
}

步骤2：添加对系统的引用。窗户。形式。您需要有一个隐藏的表单，它是键盘钩子的消息循环所必需的。

步骤3：添加以下静态类。它为您完成所有键盘挂钩的繁重工作，因此您不必这么做。

using System;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Threading;

namespace ConsoleApplication10
{
    public static class KeyListener
    {
        public static event EventHandler<HotKeyEventArgs> HotKeyPressed;

        public static int RegisterHotKey(Keys key, KeyModifiers modifiers)
        {
            _windowReadyEvent.WaitOne();
            int id = System.Threading.Interlocked.Increment(ref _id);
            _wnd.Invoke(new RegisterHotKeyDelegate(RegisterHotKeyInternal), _hwnd, id, (uint)modifiers, (uint)key);
            return id;
        }

        public static int RegisterHotKey(Keys key)
        {
            _windowReadyEvent.WaitOne();
            int id = System.Threading.Interlocked.Increment(ref _id);
            _wnd.Invoke(new RegisterHotKeyDelegate(RegisterHotKeyInternal), _hwnd, id, (uint)KeyModifiers.None, (uint)key);
            return id;
        }

        public static void UnregisterHotKey(int id)
        {
            _wnd.Invoke(new UnRegisterHotKeyDelegate(UnRegisterHotKeyInternal), _hwnd, id);
        }

        delegate void RegisterHotKeyDelegate(IntPtr hwnd, int id, uint modifiers, uint key);
        delegate void UnRegisterHotKeyDelegate(IntPtr hwnd, int id);

        private static void RegisterHotKeyInternal(IntPtr hwnd, int id, uint modifiers, uint key)
        {
            RegisterHotKey(hwnd, id, modifiers, key);
        }

        private static void UnRegisterHotKeyInternal(IntPtr hwnd, int id)
        {
            UnregisterHotKey(_hwnd, id);
        }

        private static void OnHotKeyPressed(HotKeyEventArgs e)
        {
            if (KeyListener.HotKeyPressed != null)
            {
                KeyListener.HotKeyPressed(null, e);
            }
        }

        private static volatile MessageWindow _wnd;
        private static volatile IntPtr _hwnd;
        private static ManualResetEvent _windowReadyEvent = new ManualResetEvent(false);
        static KeyListener()
        {
            Thread messageLoop = new Thread(delegate ()
            {
                Application.Run(new MessageWindow());
            });
            messageLoop.Name = "MessageLoopThread";
            messageLoop.IsBackground = true;
            messageLoop.Start();
        }

        private class MessageWindow : Form
        {
            public MessageWindow()
            {
                _wnd = this;
                _hwnd = this.Handle;
                _windowReadyEvent.Set();
            }

            protected override void WndProc(ref Message m)
            {
                if (m.Msg == WM_HOTKEY)
                {
                    HotKeyEventArgs e = new HotKeyEventArgs(m.LParam);
                    KeyListener.OnHotKeyPressed(e);
                }

                base.WndProc(ref m);
            }

            protected override void SetVisibleCore(bool value)
            {
                // Ensure the window never becomes visible
                base.SetVisibleCore(false);
            }

            private const int WM_HOTKEY = 0x312;
        }

        [DllImport("user32", SetLastError = true)]
        private static extern bool RegisterHotKey(IntPtr hWnd, int id, uint fsModifiers, uint vk);

        [DllImport("user32", SetLastError = true)]
        private static extern bool UnregisterHotKey(IntPtr hWnd, int id);

        private static int _id = 0;
    }


    public class HotKeyEventArgs : EventArgs
    {
        public readonly Keys Key;
        public readonly KeyModifiers Modifiers;

        public HotKeyEventArgs(Keys key, KeyModifiers modifiers)
        {
            this.Key = key;
            this.Modifiers = modifiers;
        }

        public HotKeyEventArgs(IntPtr hotKeyParam)
        {
            uint param = (uint)hotKeyParam.ToInt64();
            Key = (Keys)((param & 0xffff0000) >> 16);
            Modifiers = (KeyModifiers)(param & 0x0000ffff);
        }
    }

    [Flags]
    public enum KeyModifiers
    {
        None = 0,
        Alt = 1,
        Control = 2,
        Shift = 4,
        Windows = 8,
        NoRepeat = 0x4000
    }
}

步骤4：

现在，仍然有一个延迟。它更加优雅，但操作系统仍在与你抗争。那怎么办呢？

你有两个选择。

a）您实现了一个定时选项，只要计时器刻度事件上的键关闭，您只需重复该操作。您可以复制代码，也可以将其与我给您的热键方法合并。

有关详细信息，请参阅此处：删除KeyDown事件后的延迟？

private bool _moveUp;
private bool _moveDown;
private bool _moveLeft;
private bool _moveRight;

// You can add the Timer in the Winforms Designer instead if you like;
// The Interval property can be configured there at the same time, along
// with the Tick event handler, simplifying the non-Designer code here.
private System.Windows.Forms.Timer _movementTimer = new Timer { Interval = 100 };

public MainForm()
{
    InitializeComponent();

    _movementTimer.Tick += movementTimer_Tick;
}

private void movementTimer_Tick(object sender, EventArgs e)
{
    _DoMovement();
}

private void _DoMovement()
{
    if (_moveLeft) Player.MoveLeft();
    if (_moveRight) Player.MoveRight();
    if (_moveUp) Player.MoveUp();
    if (_moveDown) Player.MoveDown();
}

// You could of course override the OnKeyDown() method instead,
// assuming the handler is in the Form subclass generating the
// the event.
public void MainForm_KeyDown(object sender, KeyEventArgs e)
{
    if (e.IsRepeat)
    {
        // Ignore key repeats...let the timer handle that
        return;
    }

    switch (e.KeyCode)
    {
    case Keys.Up:
        _moveUp = true;
        break;
    case Keys.Down:
        _moveDown = true;
        break;
    case Keys.Left:
        _moveLeft = true;
        break;
    case Keys.Right:
        _moveRight = true;
        break;
    }

    _DoMovement();
    _movementTimer.Start();
}

public void MainForm_KeyUp(object sender, KeyEventArgs e)
{
    switch (e.KeyCode)
    {
    case Keys.Up:
        _moveUp = false;
        break;
    case Keys.Down:
        _moveDown = false;
        break;
    case Keys.Left:
        _moveLeft = false;
        break;
    case Keys.Right:
        _moveRight = false;
        break;
    }

    if (!(_moveUp || _moveDown || _moveLeft || _moveRight))
    {
        _movementTimer.Stop();
    }
}

b） 在Main方法中，获取延迟设置，以编程方式将延迟设置为最低设置，然后在应用程序退出时将其设置回原始设置。

有关在注册表中的位置，请参见此处：https://superuser.com/questions/388160/keyboard-repeat-rate-repeat-delay-values-in-win7

以及如何读取/写入注册表：https://msdn.microsoft.com/en-us/library/microsoft.win32.registry_methods（v=vs.110）. aspx

注意：使用这种方法，仍然有一个小延迟。它很小，但它在那里。祝你好运。