Topic 8. Encapsulation, access modifiers, and static class members

Goal: become familiar with the principle of encapsulation, access modifiers, and static members of C# classes; learn to design classes with hidden state and invariants and to use static fields, methods, constructors, and classes, as well as factory methods; master creating a solution with a class library and the internal modifier.

Lecture contents

1. Encapsulation and access modifiers — Encapsulation · Access modifiers · The assembly as an access boundary
2. Protecting state and readonly fields — Protecting object state · const, readonly, and static readonly fields
3. Static members and namespaces — Static members · Factory methods and private constructors · Namespaces and project organization
4. Examples and common mistakes — Example programs · Common mistakes

Practice and review

• Practice — 3 worked examples with complete code and output
• Tasks — 30 variants, each with tasks at three difficulty levels
• Summary — conclusions, self-check questions, and useful links