在我的控制台应用程序中，我希望能够在单声道中检测按键操作，您可以在其中获取当前按下的键列表并检查列表中是否有键，或者检测是否有键被压了。我使用
的问题if( Console.KeyAvailable ) k = Console.ReadKey( true ).Key;
是按下第一个键后会有延迟的事实。如果您打开记事本并按住＆＃34; A＆＃34;，您可以看到这样的示例。 A将被按下，然后是延迟，然后A将被发送垃圾邮件。
如何在没有按下延迟的情况下获得键盘输入？我不怕使用低级功能，例如挂钩到kernel32.dll
答案 0 :(得分：2)
所以我写了一些代码，基于我到目前为止所阅读的内容。
步骤1：将以下代码复制到控制台应用程序中。它必须是STAThread或它将引发错误。在switch语句中输入要使用的命令。 ReadKey（true）将阻止所有其他键。
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System.Windows.Forms的引用。您需要具有隐藏的表单，该表单是键盘挂钩的消息循环所必需的。
第3步：添加以下静态类。它可以为您完成所有重型键盘挂钩，因此您无需这样做。
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
}
}
第4步：
现在，仍有延迟。它更优雅，但你仍然有操作系统与你搏斗。那该怎么办？
您有两种选择。
a）您实现了一个计时选项，只要一个键在计时器刻度事件中关闭，您就可以重复该操作。您可以复制代码或将其与我给您的热键方法合并。
详情请见此处：Removing the delay after KeyDown event?
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，您将获得延迟设置，以编程方式将延迟设置为最低设置，然后在“应用程序退出”中将其设置回原始设置。
请在此处查看在注册表中找到它的位置：https://superuser.com/questions/388160/keyboard-repeat-rate-repeat-delay-values-in-win7
以及如何读/写注册表：https://msdn.microsoft.com/en-us/library/microsoft.win32.registry_methods(v=vs.110).aspx
注意：使用这种方法，仍有一点延迟。它很小，但它就在那里。祝你好运。