Beginning Visual C# 2010

Chapter 9. Defining Classes

WHAT YOU WILL LEARN IN THIS CHAPTER

• How to define classes and interfaces in C#

• How to use the keywords that control accessibility and inheritance

• What the System.Object class is and its role in class definitions

• How to use some helpful tools provided by VS and VCE

• How to define class libraries

• The differences and similarities between interfaces and abstract classes

• More about struct types

• Some important information about copying objects

In Chapter 8, you looked at the features of object-oriented programming (OOP). In this chapter, you put theory into practice and define classes in C#. You won't go so far as to define class members in this chapter, but will concentrate on the class definitions themselves. That may sound a little limiting, but don't worry—there's plenty here to get your teeth into!

To begin, you explore the basic class definition syntax, the keywords you can use to determine class accessibility and more, and the way in which you can specify inheritance. You also look at interface definitions because they are similar to class definitions in many ways.

The rest of the chapter covers various related topics that apply when defining classes in C#.

CLASS DEFINITIONS IN C#

C# uses the class keyword to define classes:

class MyClass
{
   // Class members.
}

This code defines a class called MyClass. Once you have defined a class, you are free to instantiate it anywhere else in your project that has access to the definition. By default, classes are declared as internal ...