如何防止InvokeCommandAction将事件传播到父元素？

I realised that when using an InvokeCommandAcction associated to an EventTrigger, the original event was still routing up to the parent elements until it is handled. Well, I guess it is an expected behavior. But my question is how I can mark the event as Handled so it does not propagate up through the whole UI tree?I realised that when using an InvokeCommandAcct