class HotKey
{
/// <summary>
/// 如果函数执行成功，返回值不为0。
/// 如果函数执行失败，返回值为0。要得到扩展错误信息，调用GetLastError。.NET方法:Marshal.GetLastWin32Error()
/// </summary>
/// <param name="hWnd">要定义热键的窗口的句柄</param>
/// <param name="id">定义热键ID（不能与其它ID重复） </param>
/// <param name="fsModifiers">标识热键是否在按Alt、Ctrl、Shift、Windows等键时才会生效</param>
/// <param name="vk">定义热键的内容,WinForm中可以使用Keys枚举转换，
/// WPF中Key枚举是不正确的,应该使用System.Windows.Forms.Keys枚举，或者自定义正确的枚举或int常量</param>
/// <returns></returns>
[DllImport("user32.dll", SetLastError = true)]
public static extern bool RegisterHotKey(
IntPtr hWnd,
int id,
KeyModifiers fsModifiers,
int vk
);
/// <summary>
/// 取消注册热键
/// </summary>
/// <param name="hWnd">要取消热键的窗口的句柄</param>
/// <param name="id">要取消热键的ID</param>
/// <returns></returns>
[DllImport("user32.dll", SetLastError = true)]
public static extern bool UnregisterHotKey(
IntPtr hWnd,
int id
);
/// <summary>
/// 向全局原子表添加一个字符串，并返回这个字符串的唯一标识符,成功则返回值为新创建的原子ID,失败返回0
/// </summary>
/// <param name="lpString"></param>
/// <returns></returns>
[DllImport("kernel32", SetLastError = true)]
public static extern short GlobalAddAtom(string lpString);
[DllImport("kernel32", SetLastError = true)]
public static extern short GlobalDeleteAtom(short nAtom);
/// <summary>
/// 定义了辅助键的名称（将数字转变为字符以便于记忆，也可去除此枚举而直接使用数值）
/// </summary>
[Flags()]
public enum KeyModifiers
{
None = 0,
Alt = 1,
Ctrl = 2,
Shift = 4,
WindowsKey = 8
}
/// <summary>
/// 热键的对应的消息ID
/// </summary>
public const int WM_HOTKEY = 0x312;
}

int alts,altd;
protected override void OnLoad(EventArgs e)
{
alts= HotKey.GlobalAddAtom("Alt-S");
altd= HotKey.GlobalAddAtom("Alt-D");
HotKey.RegisterHotKey(this.Handle, alts, HotKey.KeyModifiers.Alt, (int)Keys.S);
HotKey.RegisterHotKey(this.Handle, altd, HotKey.KeyModifiers.Alt, (int)Keys.D);
}
protected override void WndProc(ref Message m)// 监视Windows消息
{
switch (m.Msg)
{
case HotKey.WM_HOTKEY:
ProcessHotkey(m);//按下热键时调用ProcessHotkey()函数
break;
}
base.WndProc(ref m); //将系统消息传递自父类的WndProc
}
private void ProcessHotkey(Message m) //按下设定的键时调用该函数
{
IntPtr id = m.WParam;//IntPtr用于表示指针或句柄的平台特定类型
int sid=id.ToInt32();
if(sid==alts)
{
MessageBox.Show("按下Alt+S");
}
else if(sid==altd)
{
MessageBox.Show("按下Alt+D");
}
}

[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
var form = new Form1();
Application.AddMessageFilter(form);
Application.Run(form);
}

bool IMessageFilter.PreFilterMessage(ref Message m)
{
const int WM_HOTKEY = 0x0312;//如果m.Msg的值为0x0312那么表示用户按下了热键
switch (m.Msg)
{
case WM_HOTKEY:
ProcessHotkey(m);//按下热键时调用ProcessHotkey()函数
break;
}
//如果筛选消息并禁止消息被调度，则为 true；如果允许消息继续到达下一个筛选器或控件，则为 false
return false ;
}

int alts, altd;
private void Window_Loaded(object sender, RoutedEventArgs e)
{
HwndSource hWndSource;
WindowInteropHelper wih = new WindowInteropHelper(this);
hWndSource = HwndSource.FromHwnd(wih.Handle);
//添加处理程序
hWndSource.AddHook(MainWindowProc);
alts = HotKey.GlobalAddAtom("Alt-S");
altd = HotKey.GlobalAddAtom("Alt-D");
HotKey.RegisterHotKey(wih.Handle, alts, HotKey.KeyModifiers.Alt, (int)System.Windows.Forms.Keys.S);
HotKey.RegisterHotKey(wih.Handle, altd, HotKey.KeyModifiers.Alt, (int)System.Windows.Forms.Keys.D);
}
private IntPtr MainWindowProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
switch (msg)
{
case HotKey.WM_HOTKEY:
{
int sid = wParam.ToInt32();
if (sid == alts)
{
MessageBox.Show("按下Alt+S");
}
else if (sid == altd)
{
MessageBox.Show("按下Alt+D");
}
handled = true;
break;
}
}
return IntPtr.Zero;
}