How to programmatically create a WPF window in a WinForm application

Question

I have an existing WinForm app which is too much to port to WPF right now. However, I need a window with some tricky transparency behavior that I cannot achieve in a WinForm (yes, tried Layerd Windows but it's a no-go).

WPF allows the transparency behavior I need beautifully and simply.

I googled of course, but can only find hints how to create a WPF control within a WinForm but that is NOT what I need. I need a separate WPF window that is completely independant of my other Forms.

The WPF window will be a rather simple full-screen and borderless overlay window where I will do some simple drawings, each with different transparencies.

How can I create a WPF window within a WinForm application?

Answer 1

Add the necessary WPF references to your project, create a WPF Window-instance, call EnableModelessKeyboardInterop and show the window.

The call to EnableModelessKeyboardInterop makes sure, that your WPF window will get keyboard inputs from your Windows Forms app.

Take care, if you open a new Window from within your WPF window, the keyboard input will not be routed to this new window. You have to call also for these newly created windows EnableModelessKeyboardInterop.

Fore your other requirements, use Window.Topmost and Window.AllowsTransparency. Don't forget to set the WindowStyle to None, otherwise, transparency is not supported.

Update
The following references should be added to use WPF in your windows forms application:

• PresentationCore
• PresentationFramework
• System.Xaml
• WindowsBase
• WindowsFormsIntegration