全局监控热键

        [DllImport("user32.dll")]  //在类内部声明两个API函数
        public static extern bool RegisterHotKey(IntPtr hWnd, int id, uint control, Keys keys);

        [DllImport("user32.dll")] //在类内部声明两个API函数
        public static extern bool UnregisterHotKey(IntPtr hWnd, int id);

       public static int WmHotkey = 0x0312;  //标示用户按下了热键 

        //系统启动时注册基本事件
        protected override void OnSourceInitialized(EventArgs e)
        {
            base.OnSourceInitialized(e);
            IntPtr hWnd = new WindowInteropHelper(this).Handle; 
            RegisterHotKey(hWnd, 123, 0, Keys.F);   //注册热键
              var source = PresentationSource.FromVisual(this) as HwndSource; //获取内容
              if (source != null) source.AddHook(WndProc);  //注册处理方法
        }

        //热键处理  重写WndProc()方法,通过监视系统消息,来调用过程
        private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
        {
            if (msg != WmHotkey) return IntPtr.Zero;
            if (wParam.ToInt32() == 123)
            {
                ButtonBase_OnClick(null, null);
                handled=true;
            }
            return IntPtr.Zero;
        }

        //软件关闭时注销热键
        void Window1_Closed(object sender, EventArgs e)
        {
            IntPtr hWnd = new WindowInteropHelper(this).Handle;  
            UnregisterHotKey(hWnd, 123);
        }