How it works...

OK, let's e behind the scenes of the stuff we just completed. From steps 1 to 7, we opened an existing project and added a new Windows console application. This project is a full .NET Framework project and its version is .NET Framework version 4.6.1. In steps 9 and 10, we added the reference to a .NET Standard class library project from the Windows console application. This is required to test the class library. Then, we can reference it and use it from the application, as we did in step 12. 

In step 13, we created a variable to store the name (keep in mind, hardcoding is not a good practice). And then we have created an instance of the HelloUniverse class that we created in the .NET Standard 2.0 class library. To display the output of the SayHello() method to the console window, we have directly used the Console.WriteLine() method. Finally, we waited until the user presses a key to exit from the console by using the Console.ReadLine() method, or else the end user wouldn't be able to see any output in the console.