这是你可以发布的地方。

https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?forum=wpf

I want to create button in WPF and when I click on a button. It can open a different window which I created in a TabItem. How can I do it ???????????

It's where you can post.

https://social.msdn.microsoft.com/Forums/vstudio/en-US/home?forum=wpf