Public and Internal members in an Internal class?

Question

Ok, so this may be a bit of a silly question, and there's certainly the obvious answer, but I was curious if I've missed any subtleties here.

Is there any difference in terms of visibility/usability between a public member declared in an internal class and an internal member declared in an internal class?

i.e. between

internal class Foo
{
    public void Bar()
    {
    }
}

and

internal class Foo
{
    internal void Bar()
    {
    }
}

If you declared the method as public and also virtual, and then overrode it in a derived class that is public, the reason for using this modifier is clear. However, is this the only situation... am I missing something else?

Answer 1

public members of an internal class can override public members of public base classes and, therefore, be a little more exposed... if indirectly.

Answer 2

A public member is still just internal when in an internal class.

From MSDN:

The accessibility of a member can never be greater than the accessibility of its containing type. For example, a public method declared in an internal type has only internal accessibility

Think of it this way, I would access a public property on....? A class I can't see? :)

Eric's answer is very important in this case, if it's exposed via an interface and not directly it does make a difference, just depends if you're in that situation with the member you're dealing with.

Answer 3

Consider this case:

public interface IBar { void Bar(); }
internal class C : IBar
{
    public void Bar() { }
}

Here C.Bar cannot be marked as internal; doing so is an error because C.Bar can be accessed by a caller of D.GetBar():

public class D
{
    public static IBar GetBar() { return new C(); } 
}