Define Projection C# - WPF code example?

[RosarioBarbagallo]

Hi, i want to develop and customize "Define Projection toolbox" , I use ArcgisPro 2.4 Desktop SDK .NET (C#), but i don't

find the function on the sdk , i have find "ProjectionTransformation" but i think that it isn't corrrect.

Where can i find example or documentation C# or the code of this toolbox?

Thanks!