I'm confused about default access modifier of C# interface members
c#, clr, interface
Solution
Interfaces (C# Programming Guide)
Interfaces can contain methods, properties, events, indexers, or any combination of those four member types. For links to examples, see Related Sections. An interface can't contain constants, fields, operators, instance constructors, destructors, or types. Interface members are automatically public, and they can't include any access modifiers. Members also can't be static.
And about interface members implementation:
To implement an interface member, the corresponding member of the implementing class must be public, non-static, and have the same name and signature as the interface member.
So you can't implement an interface member using `protected` one.
Problem
What is the access modifier of `interface` methods? It should be `public` or `protected` because you have access to them when you implement them (which makes sense). It also should be `abstract` because they don't have implementation. But lately I've been reading a book called CLR Via C# and the chapter about interfaces says the following The CLR requires that `interface` methods be marked as `virtual`. If you do not explicitly mark the method as `virtual` in your source code, the compiler marks the method as `virtual` and `sealed`. When you mark the `interface` member `virtual` compiler complains that the access modifier in not valid. I mean no access modifier is valid for anything in `interface` rather than the default one which is given to them by compiler right? Can anyone make it clear for me?