Handling VirtualKey in Windows 8 Store Apps with C#

Question

I'm aware of how to handle key events, i.e.

private void Page_KeyUp(object sender, KeyRoutedEventArgs e)
{
  switch (e.Key)
  {
    case Windows.System.VirtualKey.Enter:
      // handler for enter key
      break;

    case Windows.System.VirtualKey.A:
      // handler for A key
      break;

    default:
      break;
  }
}

But what if I need to discern between lower-case 'a' and upper-case 'A'? Also, what if I want to handle keys like the percent sign '%'?

Answer 1

Got an answer elsewhere. For those that are interested...

public Foo()
{
    this.InitializeComponent();
    Window.Current.CoreWindow.CharacterReceived += KeyPress;
}

void KeyPress(CoreWindow sender, CharacterReceivedEventArgs args)
{
    args.Handled = true;
    Debug.WriteLine("KeyPress " + Convert.ToChar(args.KeyCode));
    return;
}

Even better, move the Window.Current.CoreWindow.CharacterReceived += KeyPress; into a GotFocus event handler, and add Window.Current.CoreWindow.CharacterReceived -= KeyPress; into a LostFocus event handler.

Answer 2

You can't easily get this information from KeyUp because KeyUp only knows which keys are being pressed, not which letters are being typed. You could check for the shift key being down and you could also try to track caps lock yourself. Better you use TextChanged event.