如何在同一解决方案内的多个项目中使用 C# class

Question

I'm learning C# and I don't know exactly how to make a class visible to all projects inside the Solution. Basically I have many projects, all Windows Forms, all of them have some similarity, so they can share a lot of classes. I think a good approach is put all the shared classes in the Solution folder and make all the apps get the classes from there. Is this a good approach? How to do it? Another way to do it, I think, is to put all the shared classes in one app and the others get that references.

If that is not a good approach, which one is? How to do it?

I'm using Visual Studio 2019. This is how my Solution looks like, but I can't share the classes between the projects:

Answer 1

Create a Class Library project within your solution and put your shared classes in there (right click on your solution in the Solution Explorer, Add, New Project). Then for each of the projects that you want to access the classes from, right click on Dependencies, Add Project Reference and tick the Class Library project you created.

Answer 2

You create a class library project and in there you would want to add folders where you can name them according to what the classes would do so it is easier to maintain. Then you would add your classes in the corresponding folder and in the project that you want to use the class you can add a reference to the project and the class would be accessible as long as it was a public class.