You may well find yourself wanting to attach to an event which has already been handled inside a control with no way to override and prevent the event from being handled. As seen in my prior post to this, you can make use of the AddHandler method. I am going to use the Backspace key down in a TextBox as an example, the event is only raised and not handled when the TextBox is empty. (This can be seen in the sample application in the output coming from the behavior)

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