WPF 使用全局键盘(快捷键)

方式一：使用SourceInitialized，在使用快捷键必须先注册快捷键，窗体启动并重写SourceInitialized，这个时间发生在WPF窗体的资源初始化完毕，并且可以通过WindowInteropHelper获得该窗体的句柄用来与Win32交互。

    protected override void OnSourceInitialized(EventArgs e)
    {
        base.OnSourceInitialized(e);
        //注册快捷键热键
        HotKey k = new HotKey(this, HotKey.KeyFlags.MOD_ALT, System.Windows.Forms.Keys.D);
        k.OnHotKey += new HotKey.OnHotkeyEventHandeler(ScreenShotHotKey);
    }
    //快捷键启动事件
    private void ScreenShotHotKey()
    {
         MessageBox.Show("启动截图");
    }

方式二：Window_KeyDown,KeyEventArgs对象包含一个KeyStates属性，该属性反映触发事件的键的属性,KeyboardDevice属性为键 盘上的所有键提供了相同的信息，自然也提供了一个KeyboardDevice类的一个实例。它的属性包括当前是哪个元素具有焦点，以及当事件发生时按下了哪些修饰键（Modifiers）包括Shift、Ctrl、Alt键，并且使用位逻辑来检查它们的状态。

 
 

//快捷键
private void Window_KeyDown(object sender, KeyEventArgs e)
{
    /*
     if ((e.KeyboardDevice.Modifiers & ModifierKeys.Control) == ModifierKeys.Control&&e.Key==Key.D1)
      {
           //将要执行代码
      }
     */
      if (e.KeyStates == Keyboard.GetKeyStates(Key.D) && Keyboard.Modifiers == ModifierKeys.Alt)
      {
                MessageBox.Show("您按下了键");
      }
}
 

方式三：使用钩子，需要引用 System.Windows.Forms

    
        
        
    



/// 

/// Window1.xaml 的交互逻辑后台代码
/// 
public partial class Window1 : Window
{
    /// 声明回调函数委托  
    ///   
    ///   
    ///   
    ///   
    ///   
    public delegate int HookProc(int nCode, Int32 wParam, IntPtr lParam);

    /// 
  
    /// 委托实例  
    /// 
  
    HookProc KeyboardHookProcedure;

    /// 
  
    /// 键盘钩子句柄  
    /// 
  
    static int hKeyboardHook = 0;

    //装置钩子的函数   
    [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
    public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);

    //卸下钩子的函数   
    [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
    public static extern bool UnhookWindowsHookEx(int idHook);

    //获取某个进程的句柄函数  
    [DllImport("kernel32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
    private static extern IntPtr GetModuleHandle(string lpModuleName);

    /// 
  
    /// 普通按键消息  
    /// 
  
    private const int WM_KEYDOWN = 0x100;
    /// 
  
    /// 系统按键消息  
    /// 
  
    private const int WM_SYSKEYDOWN = 0x104;

    //鼠标常量   
    public const int WH_KEYBOARD_LL = 13;

    //声明键盘钩子的封送结构类型   
    [StructLayout(LayoutKind.Sequential)]
    public class KeyboardHookStruct
    {
        public int vkCode; //表示一个在1到254间的虚似键盘码   
        public int scanCode; //表示硬件扫描码   
        public int flags;
        public int time;
        public int dwExtraInfo;
    }

    public Window1()
    {
        InitializeComponent();
    }
        
    /// 
  
    /// 截取全局按键，发送新按键，返回  
    /// 
  
    ///   
    ///   
    ///   
    ///   
    private int KeyboardHookProc(int nCode, Int32 wParam, IntPtr lParam)
    {
        if (nCode >= 0 && wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN)
        {
            KeyboardHookStruct MyKeyboardHookStruct = (KeyboardHookStruct)Marshal.PtrToStructure(lParam, typeof(KeyboardHookStruct));
            System.Windows.Forms.Keys keyData = (System.Windows.Forms.Keys)MyKeyboardHookStruct.vkCode;

            if (keyData == System.Windows.Forms.Keys.D && (int)System.Windows.Forms.Control.ModifierKeys == (int)System.Windows.Forms.Keys.Control)
            {
                MessageBox.Show("你按下了Ctrl+D");
                //return为了屏蔽原来的按键，如果去掉，则原来的按键和新的按键都会模拟按。  
                return 1;
            }
        }
        return 0;
    }

    private void BtnStart_Click(object sender, RoutedEventArgs e)
    {
        //启动键盘钩子   
        if (hKeyboardHook == 0)
        {
            //实例化委托  
            KeyboardHookProcedure = new HookProc(KeyboardHookProc);
            Process curProcess = Process.GetCurrentProcess();
            ProcessModule curModule = curProcess.MainModule;
            hKeyboardHook = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardHookProcedure, GetModuleHandle(curModule.ModuleName), 0);
        }
    }

    /// 
  
    /// 停止键盘钩子  
    /// 
  
    ///   
    ///   
    private void BtnStop_Click(object sender, EventArgs e)
    {
        bool retKeyboard = true;

        if (hKeyboardHook != 0)
        {
            retKeyboard = UnhookWindowsHookEx(hKeyboardHook);
            hKeyboardHook = 0;
        }
        //如果卸下钩子失败   
        if (!(retKeyboard)) throw new Exception("卸下钩子失败！");
    }


}