WPF中的全局热键在每个窗口中工作

时间:2012-07-07 19:22:29

标签: c# wpf hotkeys

我必须使用热键,它将在每个窗口和讲坛上工作。在winforms我用过:

RegisterHotKey(this.Handle, 9000, 0x0002, (int)Keys.F10);

UnregisterHotKey(this.Handle, 9000);

protected override void WndProc(ref Message m)
{
    base.WndProc(ref m);
    switch (m.Msg)
    {
        case 0x312:
        switch (m.WParam.ToInt32())
        {
            case 9000:
            //function to do
            break;
        }
        break;
    }
}

在我的WPF应用程序中,我尝试过:

AddHandler(Keyboard.KeyDownEvent, (KeyEventHandler)HandleKeyDownEvent);

private void HandleKeyDownEvent(object sender, KeyEventArgs e)
{
    if (e.Key == Key.F11 && (Keyboard.Modifiers & ModifierKeys.Control) == ModifierKeys.Control)
    {
        //function to do
    }
}    

但它仅在我的应用程序处于活动状态且位于顶部时才起作用,但在应用程序最小化时(例如)它不起作用。有什么方法可以做到吗?

1 个答案:

答案 0 :(得分:28)

您可以使用与WinForms中相同的方法进行一些调整:

  • 使用WindowInteropHelper获取HWND(而不是表单的Handle属性)
  • 使用HwndSource处理窗口消息(而不是覆盖表单的WndProc
  • 不要使用Key中的WPF枚举 - 它的值不是您想要的值

完整代码:

[DllImport("User32.dll")]
private static extern bool RegisterHotKey(
    [In] IntPtr hWnd,
    [In] int id,
    [In] uint fsModifiers,
    [In] uint vk);

[DllImport("User32.dll")]
private static extern bool UnregisterHotKey(
    [In] IntPtr hWnd,
    [In] int id);

private HwndSource _source;
private const int HOTKEY_ID = 9000;

protected override void OnSourceInitialized(EventArgs e)
{
    base.OnSourceInitialized(e);
    var helper = new WindowInteropHelper(this);
    _source = HwndSource.FromHwnd(helper.Handle);
    _source.AddHook(HwndHook);
    RegisterHotKey();
}

protected override void OnClosed(EventArgs e)
{
    _source.RemoveHook(HwndHook);
    _source = null;
    UnregisterHotKey();
    base.OnClosed(e);
}

private void RegisterHotKey()
{
    var helper = new WindowInteropHelper(this);
    const uint VK_F10 = 0x79;
    const uint MOD_CTRL = 0x0002;
    if(!RegisterHotKey(helper.Handle, HOTKEY_ID, MOD_CTRL, VK_F10))
    {
        // handle error
    }
}

private void UnregisterHotKey()
{
    var helper = new WindowInteropHelper(this);
    UnregisterHotKey(helper.Handle, HOTKEY_ID);
}

private IntPtr HwndHook(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
    const int WM_HOTKEY = 0x0312;
    switch(msg)
    {
        case WM_HOTKEY:
            switch(wParam.ToInt32())
            {
                case HOTKEY_ID:
                    OnHotKeyPressed();
                    handled = true;
                    break;
            }
            break;
    }
    return IntPtr.Zero;
}

private void OnHotKeyPressed()
{
    // do stuff
}