WPF rectangle - round just top corners

Question

How can I have just the top corners rounded for a WPF rectangle?

I created a border and set the CornerRadius property and inside the border I\'ve added my

Answer 1

The problem you've got is that the rectangle is "overflowing" the rounded corners of your border.

A rectangle can't have individually rounded corners, so if you just put the background colour on the border and remove the rectangle:

You'll get your desired effect.