Question

Interface is a contract between client and server and it is necessary for a server to define or implement methods declared in interface. This is definition of internal and I believe that it means Interface should be public only, but while creating Interface when I use internal keyword before interface it works fine and doesn’t give me any compile time error, but I didn’t understand why.

Edit : Even if we can declare interface as internal it is necessary for a class method implementing interface member to be public. Why this?

Answer 1

The internal keyword means that the class or interface can only be used by other classes within the same assembly.

http://msdn.microsoft.com/en-us/library/7c5ka91b(VS.80).aspx

An interface is not necessarily a contract between two clients or servers, but rather it’s a promise that an object will implement certain methods or properties.

http://msdn.microsoft.com/en-us/library/87d83y5b(v=VS.71).aspx