Microsoft Visual C# 2013 Step by Step

Chapter 13. Creating interfaces and defining abstract classes

After completing this chapter, you will be able to:

• Defining an interface

• Implementing an interface

• Referencing a class through its interface

• Abstract classes

• Sealed classes

Inheriting from a class is a powerful mechanism, but the real power of inheritance comes from inheriting from an interface. An interface does not contain any code or data; it just specifies the methods and properties that a class that inherits from the interface must provide. Using an interface makes it possible for you to completely separate the names and signatures of the methods of a class from the method’s implementation.

Abstract classes are similar in many ways to interfaces except that they can contain code and ...