2 classes implement same interface, duplicated code

Question

I have an interface:

public interface IUser
{

}

And then 2 classes that implement this interface:

public class User : IUser 
{

}

public class AdminUser : IUser
{

}

Now the problem I see is that there is duplicate code between User and AdminUser when implementing a method in the interface.

Can I introduce an abstract class that would implement the common code between User and AdminUser somehow?

I don't want AdminUser to inherit from User.

Answer 1

Yes. You can.

public abstract class BaseUser : IUser
{

}

public class User : BaseUser 
{

}

public class AdminUser : BaseUser
{

}

Answer 2

Sounds like you should introduce a UserBase class that both User and AdminUser could inherit from that has the shared code

class UserBase : IUser { 

  // Shared Code

}

class User : UserBase { } 

class AdminUser : UserBase { }