Question: In Win Form, we can create non-rectangular forms by creating a bitmap that have a background color like blue. So, we can set it to background image of Win Form and with change TransparencyKey option to blue, we have a shaped-window.

So, my question is `What is the equivalency to TransparencyKey in WPF that does like Win Form's TransparencyKey?`

Thanks for your attention :)

Answer: 
There is no equivalent.  

Just use an image with transparent areas (so it has to be a PNG or GIF), set the `WindowStyle` to `None`, set the window's background to `Transparent`, and set `AllowTransparency` to true.

Transparent areas will not be clickable.
Set AllowTransparency to true then use pixel shader effect library for wpf.
Use this link for more details about how to use pixel shader : [Green screen in wpf](https://stackoverflow.com/questions/5200851/green-screen-in-wpf)