I have been developing Windows Forms programs for few years. I am now looking into .NET Core (including ASP.NET Core MVC). I am searching for the new GUI desktop technology.
For creating a console-based UI, you can use gui.cs. It is open-source (from Miguel de Icaza, creator of Xamarin), and runs on .NET Core on Windows, Linux, and macOS.
It has the following components:
Sample screenshot