C#_注册系统全局快捷键

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Runtime.InteropServices;

public class HotKeys
{
int keyid = 10;
Dictionary<int, HotKeyCallBackHanlder> keymap = new Dictionary<int, HotKeyCallBackHanlder>();
public  delegate void HotKeyCallBackHanlder();
public  enum HotkeyModifiers
{
Alt = 1,
Control = 2,
Shift = 4,
Win = 8
}
[DllImport("user32.dll")]
static extern bool RegisterHotKey(IntPtr hWnd, int id, int modifiers, Keys vk);

[DllImport("user32.dll")]
static extern bool UnregisterHotKey(IntPtr hWnd, int id);

/// <summary>
/// 注册快捷键
/// </summary>
/// <param name="hWnd">持有快捷键窗口的句柄</param>
/// <param name="fsModifiers">组合键</param>
/// <param name="vk">快捷键的虚拟键码</param>
/// <param name="callBack">回调函数（按下快捷键时被调用的方法）</param>
public void Regist(IntPtr hWnd, int modifiers, Keys vk, HotKeyCallBackHanlder callBack)
{
int id = keyid++;
if (!RegisterHotKey(hWnd, id, modifiers, vk))
throw new Exception("注册失败！");
keymap[id] = callBack;
}

/// <summary>
/// 注销快捷键
/// </summary>
/// <param name="hWnd">持有快捷键窗口的句柄</param>
/// <param name="callBack">回调函数</param>
public  void UnRegist(IntPtr hWnd, HotKeyCallBackHanlder callBack)
{
foreach (KeyValuePair<int, HotKeyCallBackHanlder> var in keymap)
{
if (var.Value == callBack)
UnregisterHotKey(hWnd, var.Key);
}
}

/// <summary>
/// 快捷键消息处理
/// </summary>
public void ProcessHotKey(Message m)
{
if (m.Msg == 0x312)
{
int id = m.WParam.ToInt32();
HotKeyCallBackHanlder callback;
if (keymap.TryGetValue(id, out callback))
callback();
}
}
}

HotKeys h = new HotKeys();

//窗体登录时注册快捷键
private void Form2_Load(object sender, EventArgs e)
{
//这里注册了Ctrl+Alt+E 快捷键
h.Regist(this.Handle, (int)HotKeys.HotkeyModifiers.Control + (int)HotKeys.HotkeyModifiers.Alt, Keys.E, CallBack);
MessageBox.Show("注册成功");
}

//按钮点击卸载
private void button1_Click(object sender, EventArgs e)
{
h.UnRegist(this.Handle, CallBack);
MessageBox.Show("卸载成功");
}

//重载WndProc函数
protected override void WndProc(ref Message m)
{
h.ProcessHotKey(m);//快捷键消息处理
base.WndProc(ref m);
}

//按下快捷键时被调用的方法
public  void CallBack()
{
MessageBox.Show("快捷键被调用！");
}