Join 2 classes - essentially

Question

I've got a .NET Web Service Reference to a 3rd party WSDL.

In that reference are 2 classes. Basically these 2 classes are most likely Interfaces on the 3rd Party API side but in .NET end up as 2 proxy classes.

I have a need to combine both these classes into one class. Why? Because it's stupid that these are split, they're the service which allows me to make method calls. The method calls are all split half and half between these 2 proxy classes.

So I want to create a custom wrapper class called ThirdPartyService and somehow essentially inherit both those proxy class's members. I know you can inherit 2 classes in C# but I don't see how to do this with an interface either.

Answer 1

Well, you haven't given us a lot to work with, but you could do this using composition.

class Foo {
    public void Frobber();
}

class Bar {
    public void Blorb();
}

Then

class FooAndBar {
    Foo _foo;
    Bar _bar;
    public FooAndBar(Foo foo, Bar bar) {
        _foo = foo;
        _bar = bar;
    }

    public void Frobber() { _foo.Frobber(); }
    public void Blorb() { _bar.Blorb(); }
}

If Foo and Bar implement interfaces IFoo and IBar respectively then you can have FooAndBar implement IFoo and IBar too.

In the language of Design Patterns we would call this the adapter pattern.

Regarding your edit:

I know you can inherit 2 classes in C# but I don't see how to do this with an interface either.

No. You can not inherit from two classes in C#. You have to use composition like I already explained.

Answer 2

Maybe to add some value to Jason's post, this sort of stuff would also be known as adapter