How to: Create Inheritance Between Types (Class Designer)
To create an inheritance relationship between two types on a class diagram using Class Designer, connect the base type with its derived type or types. You can have an inheritance relationship between two classes, between a class and an interface, or between two interfaces.
To create an inheritance between types
From your project in Solution Explorer, open a class diagram (.cd) file.
If you don't have a class diagram, create it. See How to: Add Class Diagrams to Projects.
In the Toolbox, under Class Designer, click Inheritance.
On the class diagram, draw an inheritance line between the types that you want, starting from:
A derived class to the base class
An implementing class to the implemented interface
An extending interface to the extended interface
Optionally, when you have a derived type from a generic type, click the inheritance line. In the Properties window, set the Type Arguments property to match the type that you want for the generic type.
If a parent abstract class contains at least one abstract member, then all abstract members are implemented as non-abstract inheriting classes.
Although you can visualize existing generic types, you can't create new generic types. You also can't change the type parameters for existing generic types.