【问题】
一个C#窗体程序，想要实现，不论程序是否获得当前焦点，都要能够捕获到全局的某个设置好的快捷键。
比如按Ctrl+Alt+Shift+M，然后程序就可以捕获到。
【解决过程】
1.从这里：c#全局热键+获取窗口句柄，得知有个RegisterHotKey的。
2.然后就找到这里：Set global hotkeys using C#，参考其代码，去添加了如下代码：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace downloadSongtasteMusic
{
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
}
public partial class frmDownloadSonstasteMusic : Form
{
KeyboardHook hook = new KeyboardHook();
public frmDownloadSonstasteMusic()
{
InitializeComponent();
// register the event that is fired after the key press.
hook.KeyPressed += new EventHandler<KeyPressedEventArgs>(hook_KeyPressed);
// register the control + alt + F12 combination as hot key.
hook.RegisterHotKey(ModifierKeys.Control | ModifierKeys.Alt, Keys.F12);
}
private void frmDownloadSonstasteMusic_Load(object sender, EventArgs e)
{
}
private void frmDownloadSonstasteMusic_SizeChanged(object sender, EventArgs e)
{
if (this.WindowState == FormWindowState.Minimized)
{
Hide(); // 隐藏窗体
nfiSystem.Visible = true; // 系统托盘图标可见
}
}
private void nfiSystem_MouseDoubleClick(object sender, MouseEventArgs e)
{
this.Visible = true;
this.WindowState = FormWindowState.Normal;
this.nfiSystem.Visible = false;
}
}
}结果编译出错：
D:\xxx\downloadSongtasteMusic\frmDownloadSonstasteMusic.cs(15,10): error CS0246: The type or namespace name ‘DllImport’ could not be found (are you missing a using directive or an assembly reference?)
然后就先去解决DllImport的问题。
3.然后解决了上述DllImport的问题：
4.接着编译又出现了错误，是关于上述代码中的ModifierKeys，折腾了一下，发现好像是和系统自带的ModifierKeys有冲突，所以自己将其改为ModifierKeys_e，然后才解决问题。
其中，还由于把上面一堆代码，拷贝到当前那个窗体对应的cs文件：frmDownloadSonstasteMusic.cs中，无法工作，然后把这代码都放到另外的一个文件Program.cs，然后才可以正常使用，窗体才可以正常显示。
然后运行了一下，同时按Ctrl+Alt+F12，就可以捕获，并在texBox中显示出来了。
最后工作的代码是：
（1）Program.cs
using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace downloadSongtasteMusic
{
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_e modifier = (ModifierKeys_e)((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_e 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_e _modifier;
private Keys _key;
internal KeyPressedEventArgs(ModifierKeys_e modifier, Keys key)
{
_modifier = modifier;
_key = key;
}
public ModifierKeys_e Modifier
{
get { return _modifier; }
}
public Keys Key
{
get { return _key; }
}
}
/// <summary>
/// The enumeration of possible modifiers.
/// </summary>
[Flags]
public enum ModifierKeys_e : uint
{
Alt = 1,
Control = 2,
Shift = 4,
Win = 8
}
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new frmDownloadSonstasteMusic());
}
}
}（2）frmDownloadSonstasteMusic.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace downloadSongtasteMusic
{
public partial class frmDownloadSonstasteMusic : Form
{
KeyboardHook hook = new KeyboardHook();
public frmDownloadSonstasteMusic()
{
InitializeComponent();
// register the event that is fired after the key press.
hook.KeyPressed += new EventHandler<KeyPressedEventArgs>(hook_KeyPressed);
// register the control + alt + F12 combination as hot key.
//hook.RegisterHotKey(ModifierKeys.Control | ModifierKeys.Alt, Keys.F12);
hook.RegisterHotKey(ModifierKeys_e.Control | ModifierKeys_e.Alt, Keys.F12);
}
void hook_KeyPressed(object sender, KeyPressedEventArgs e)
{
// show the keys pressed in a label.
rtbInfo.Text = e.Modifier.ToString() + " + " + e.Key.ToString();
}
private void frmDownloadSonstasteMusic_Load(object sender, EventArgs e)
{
}
private void frmDownloadSonstasteMusic_SizeChanged(object sender, EventArgs e)
{
if (this.WindowState == FormWindowState.Minimized)
{
Hide(); // 隐藏窗体
nfiSystem.Visible = true; // 系统托盘图标可见
}
}
private void nfiSystem_MouseDoubleClick(object sender, MouseEventArgs e)
{
this.Visible = true;
this.WindowState = FormWindowState.Normal;
this.nfiSystem.Visible = false;
}
}
}转载请注明：在路上 » 【已解决】C#中如何注册/获得/捕获全局热键/快捷键