Microsoft Visual C# Step by Step, Ninth Edition

CHAPTER 13

Creating interfaces and defining abstract classes

After completing this chapter, you will be able to:

• Define an interface specifying the signatures and return types of methods.

• Implement an interface in a structure or class.

• Reference a class through an interface.

• Capture common implementation details in an abstract class.

• Implement sealed classes that cannot be used to derive new 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. By using an interface, you can completely separate the names and signatures ...