Framework Design Guidelines: Conventions, Idioms, and Patterns for Reusable .NET Libraries, 3rd Edition

4

Type Design Guidelines

From the CLR perspective, there are only two categories of types— reference types and value types—but for the purpose of discussing framework design, we divide types into more logical groups, each with its own specific design rules. Figure 4-1 shows these logical groups.

Figure 4-1: The logical grouping of types

Classes are the general case of reference types. They make up the bulk of types in the majority of frameworks. Classes owe their popularity to the rich set of object-oriented features they support and to their general applicability. Base classes and abstract classes are special logical groups related to extensibility. ...