I once saw the source code of a winform application and the code had a Console.WriteLine();. I asked the reason for that and i was told that it was for
You wouldn't really use it normally but if you've attached a Console or use AllocConsole, it will function like in any other console application and the output will be visible there.
For quick debugging, I prefer Debug.WriteLine but for a more robust solution, the Trace class may be preferable.