C# generic ClientBase with interface confusion

Question

The C# definition of ClientBase is:

public abstract class ClientBase : ICommunicationObject, 
    IDisposable
where TChannel : class
<         


        

Answer 1

The class constraint constraints the generic type to a reference type. An interface is, by definition, a reference type. What you can't do is use a value type as the generic type: ClientBase<int> would be a compile time error.

As to the second error, you are not constraining TInterface and then using it inClientBase<TInterface>. Because ClientBase constraints its generic type to reference types (class), you need to constraint TInterface accordingly.