wpf - Find out source of raised Routed Event -

I have a little problem. I do not know why my control firing events twice. I know that something on the stack overflow The time was discussed, but still I could not find the reason.

What is the main reason for debugging and raising the application? I'm not good at this moment (at the moment), but this is a good way.

thx

When you wait for a more accurate answer, check Take that you have not added the event handler twice