Question

I’m facing a problem regarding multiple inheritance in VB.net:

As far as I know VB.net does not support multiple inheritance in general but you can reach a kind of multiple inheritance by working with interfaces (using “Implements” instead of “Inherits”):

Public Class ClassName
    Implements BaseInterface1, BaseInterface2

End Class

That works fine for classes but I’d like to have an interface inheriting some base interfaces. Something like that:

Public Interface InterfaceName
    Implements BaseInterface1, BaseInterface2

End Interface

But the “Implements” keyword is not allowed for interfaces (what makes sense, of course). I tried to use a kind of abstract class which I know from Java:

Public MustInherit Class InterfaceName
    Implements BaseInterface1, BaseInterface2

End Class

But now I need to implement the defined methods from BaseInterface1 and BaseInterface2 within the InterfaceName class. But as InterfaceName should be an interface, too, I don’t want to have to implement these methods within that class.

In C# you can do that quite easy:

public interface InterfaceName: BaseInterface1, BaseInterface2 {}

Do you know if I can do something similar in VB.net?

Answer 1

Similar to Java, in VB.NET interfaces “extend” other interfaces. That means they “inherit” their functionality. They do not implement it.

Public Interface InterfaceName
    Inherits BaseInterface1, BaseInterface2
End Interface