Find Docking a Window to Left/Right Side

Find Docking a Window to Left/Right Side

Is there any way to find out an EVENT (or property or method or something
like) for detect Window Docking to Left or Right Side?
Description:
With WindowState property you can find out, when you windows changed state
between these three states Normal / Minimized / Maximized. After Windows
7, you can have two kind of docking "Dock To Left" and "Dock To Right". I
can't find any property or event in Window Class.
You Can dock a Window to left with WinKey + Left or dock a Window to right
with WinKey + Right.
Question:
I need to have some changes in my window after docking to left or right. I
need one trigger in WPF/XAML but i can't find any property or event
related to Docking to left/right.