Beginning C# 2008 Objects: From Concept to Code

5.5. Summary

In this chapter, you learned

• That an association describes a relationship between classes—that is, a potential relationship between objects of two particular types/classes.

• That we define the multiplicity of an association between classes X and Y in terms of how many objects of type X can be linked to a given object of type Y, and vice versa. Possible multiplicities are one-to-one (1:1), one-to-many (1:m), and many-to-many (m:m). In all these cases, the involvement of the objects at either end of the relationship may be optional or mandatory.

• That an aggregation is a special type of association that implies containment.

• How to derive new classes based on existing classes through inheritance and what the do's and don'ts are when deriving ...