what happens when an object derives from MarshalByRefObject and is also marked [Serializable]?

Question

I'm working on my first project that uses AppDomains and I'm wondering what happens when an object derives from MarshalByRefObject and is also marked [Serializable]?

for example:

[Serializable]
public class DummyClass: MarshalByRefObject
{

}

Answer 1

It gets marshalled by reference, but can still be serialised for other use-cases for serialisation. There's an implementation detail to this that is interesting enough to be worth noting: The formatter that is serialising for remoting uses a SurrogateSelector that will produce a proxy for any MarshalByRefObject it serialises, hence serialising will still result in marshalling by reference. Other serialisation uses won't have that SurrogateSelector and so won't have that effect.