Silverlight mouse button up outside control

I have a made a simple UserControl that allows a user to drag a button around and drop it. It uses MouseLeftButtonDown and MouseLeftButtonUp to start and stop dragging.

The problem is, however, that MouseLeftButtonUp is开发者_StackOverflow社区 only triggered when the mouse is actualy on my UserControl.

How can I catch 'global' mouse events on this UserControl?

Thanks!

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Take a look at the CaptureMouse method (Silverlight 3+) here.