我正在使用 user32.dll 中的“RegisterHotKey”注册一个热键按下热键将触发一个事件,该事件执行 Console.WriteLine("HOTKEY");
正常工作,但我遇到了一个问题,大约 5 秒后它停止工作。事件不再触发。通过注释掉,我将其缩小到 1 行代码: Process[] p = Process.GetProcessesByName("notepad"); 即获取进程名称(名称无关紧要,记事本或任何东西)
此 GetProcessesByName 在 System.Timers 计时器上每秒调用一次。就像我说的,大约 5 秒后(有时是 3 或 4 秒,它是随机的)热键停止工作。
我怎样才能解决这个问题?
下面是我正在使用的代码(来自这个网站)
问题可能与 RegisterHotKey 的第一个参数有关吗?(一个 HWND)我必须有一个活跃的表格来注册热键吗?
public class HotkeyController {
public HotkeyController() {
KeyboardHook k = new KeyboardHook();
k.RegisterHotKey(0, Keys.Subtract);
k.KeyPressed += new EventHandler<KeyPressedEventArgs>(k_KeyPressed);
}
void k_KeyPressed(object sender, KeyPressedEventArgs e) {
Console.WriteLine("HOTKEY");
}
}
public sealed class KeyboardHook : IDisposable {
// Registers a hot key with Windows.
[DllImport("user32.dll")]
private static extern bool RegisterHotKey(IntPtr hWnd, int id, uint fsModifiers, uint vk);
// Unregisters the hot key with Windows.
[DllImport("user32.dll")]
private static extern bool UnregisterHotKey(IntPtr hWnd, int id);
/// <summary>
/// Represents the window that is used internally to get the messages.
/// </summary>
private class Window : NativeWindow, IDisposable {
private static int WM_HOTKEY = 0x0312;
public Window() {
// create the handle for the window.
this.CreateHandle(new CreateParams());
}
/// <summary>
/// Overridden to get the notifications.
/// </summary>
/// <param name="m"></param>
protected override void WndProc(ref Message m) {
base.WndProc(ref m);
// check if we got a hot key pressed.
if (m.Msg == WM_HOTKEY) {
// get the keys.
Keys key = (Keys)(((int)m.LParam >> 16) & 0xFFFF);
ModifierKeys modifier = (ModifierKeys)((int)m.LParam & 0xFFFF);
// invoke the event to notify the parent.
if (KeyPressed != null)
KeyPressed(this, new KeyPressedEventArgs(modifier, key));
}
}
public event EventHandler<KeyPressedEventArgs> KeyPressed;
#region IDisposable Members
public void Dispose() {
this.DestroyHandle();
}
#endregion
}
private Window _window = new Window();
private int _currentId;
public KeyboardHook() {
// register the event of the inner native window.
_window.KeyPressed += delegate(object sender, KeyPressedEventArgs args) {
if (KeyPressed != null)
KeyPressed(this, args);
};
}
/// <summary>
/// Registers a hot key in the system.
/// </summary>
/// <param name="modifier">The modifiers that are associated with the hot key.</param>
/// <param name="key">The key itself that is associated with the hot key.</param>
public void RegisterHotKey(ModifierKeys modifier, Keys key) {
// increment the counter.
_currentId = _currentId + 1;
// register the hot key.
if (!RegisterHotKey(_window.Handle, _currentId, (uint)modifier, (uint)key))
throw new InvalidOperationException("Couldn’t register the hot key.");
}
/// <summary>
/// A hot key has been pressed.
/// </summary>
public event EventHandler<KeyPressedEventArgs> KeyPressed;
#region IDisposable Members
public void Dispose() {
// unregister all the registered hot keys.
for (int i = _currentId; i > 0; i--) {
UnregisterHotKey(_window.Handle, i);
}
// dispose the inner native window.
_window.Dispose();
}
#endregion
}
/// <summary>
/// Event Args for the event that is fired after the hot key has been pressed.
/// </summary>
public class KeyPressedEventArgs : EventArgs {
private ModifierKeys _modifier;
private Keys _key;
internal KeyPressedEventArgs(ModifierKeys modifier, Keys key) {
_modifier = modifier;
_key = key;
}
public ModifierKeys Modifier {
get { return _modifier; }
}
public Keys Key {
get { return _key; }
}
}
/// <summary>
/// The enumeration of possible modifiers.
/// </summary>
[Flags]
public enum ModifierKeys : uint {
Alt = 1,
Control = 2,
Shift = 4,
Win = 8
}