Professional C# and .NET, 2021st Edition

4Object-Oriented Programming in C#

WHAT'S IN THIS CHAPTER?

• Using inheritance with classes and records
• Working with access modifiers
• Using interfaces
• Working with default interface methods
• Using dependency injection
• Using generics

CODE DOWNLOADS FOR THIS CHAPTER

The source code for this chapter is available on the book page at www.wiley.com. Click the Downloads link. The code can also be found at https://github.com/ProfessionalCSharp/ProfessionalCSharp2021 in the directory 1_CS/ObjectOrientation.

The code for this chapter is divided into the following major examples:

• VirtualMethods
• AbstractClasses
• InheritanceWithConstructors
• RecordsInheritance
• UsingInterfaces
• DefaultInterfaceMethods
• GenericTypes
• GenericTypesWithConstraints

All the projects have nullable reference types enabled.

OBJECT ORIENTATION

C# is not a pure object-oriented programming language because it offers multiple programming paradigms. However, object orientation is an important concept with C#; it's a core principle of all the libraries offered by .NET.

The three most important concepts of object orientation are inheritance, encapsulation, and polymorphism. Chapter 3, “Classes, Records, Structs, and Tuples,” talks about creating individual types to arrange properties, methods, and fields. When members of a type are declared private, they cannot be accessed from the outside. They are encapsulated within the type. This chapter covers inheritance and polymorphism and extends encapsulation features ...