Hide Console Window in C# Console Application

Change the output type from Console Application to Windows Application. This can be done under Project -> Properties -> Application in Visual Studio:

Change your application type to a windows application. Your code will still run, but it will have no console window, nor standard windows window unless you create one.

Instead of Console.Readline/key you can use new ManualResetEvent(false).WaitOne() at last. This works well for me.