WPF WindowsFormsHost不会冒泡未处理的关键手势

Ok, I'm not sure I understand how this should work, but in my app I have bound a key gesture (Ctrl+K) to a RoutedCommand. No matter where I focus in my app, the key combination works, except if I use it inside of a WindowsFormsHost containing a web browser control. I tried capturing the PreviewKeyDown event for the web browser control and setting the IsInputKey to false. This should, in theory, cause the Host to consider the key gesture untreated and send it upwards, but that doesn't happen.Ok, I'm not sure I understand how this should w