I have a question while studying C#.
When I declare the interface, I usually declare it like the code below
public interface IRequireInitialization
{
void Init();
}
public class TESTManager : IRequireInitialization
{
public void Init(){ throw new NotImplementedException(); }
}
but my friend said that I should add abstract before the declaration of the interface member function.
I didn’t feel any big difference in implementing the interface, what’s the difference? And if there is a difference, when should I use it?
public interface IRequireInitialization
{
abstract void Init();
}
public class TESTManager : IRequireInitialization
{
public void Init(){ throw new NotImplementedException(); }
}
>Solution :
C# 8 introduced default interface methods. This allows to define a default implementation (body) for a method in the interface itself.
As part of this proposal they relaxed the syntax to allow modifiers for interface methods:
The syntax for an interface is relaxed to permit modifiers on its members. The following are permitted: private, protected, internal, public, virtual, abstract, sealed, static, extern, and partial.
A method in an interface is abstract by default and abstract modified just makes that explicit:
similarly, although abstract is the default on interface members without bodies, that modifier may be given explicitly.