Question

I have a problem that I have two types, and the difference is just in a signiture of a method. My ‘Plan-B’ is that forget this difference and I handle it in the concrete implementation, but for ‘Plan-A’ I want the following:

public interface MyInterface
{
    int property;
    void MyMethod();
    ICollection<int> MyMethod();
}

public interface A : MyInterface
{
    void MyMethod();
}

public class AClass : A
{
    public void MyMethod() { ... }
}

public interface B : MyInterface
{
    ICollection<int> MyMethod();
}

public class BClass : B
{
    public ICollection<int> MyMethod() { ... }
}

So I want that AClass has to be implement methods from A, and do not have to implement ICollection MyMethod from MyInterface.

I hope I wrote it clear.

Is it possible?

Thank you!

Answer 1

Not sure I understand precisely, but try this:

public interface MyInterface
{
    int property;
}

public interface A : MyInterface
{
    void MyMethod();
}

public class AClass : A
{
    public void MyMethod() { ... }
    int property;
}

public interface B : MyInterface
{
    ICollection<int> MyMethod();
}

public class BClass : B
{
    public ICollection<int> MyMethod() { ... }
    int property;
}

In other words, interface A adds the method void MyMethod() to interface MyInterface, and interface B adds the method ICollection<int> MyMethod() to interface MyInterface.

Note that you still won’t be able to call e.g.

MyInterface object = new AClass();
object.MyMethod();

as MyMethod() won’t be a member of MyInterface.