In this chapter you’ll:
Understand how polymorphism enables you to “program in the general” and make systems extensible.
Use overridden methods to effect polymorphism.
Create abstract classes and methods.
Determine an object’s type at execution time with operator is
, then use downcasting to perform type-specific processing.
Create sealed
methods and classes.
Declare and implement interfaces.
Be introduced to interfaces IComparable
, IComponent
, IDisposable
and IEnumerator
of the .NET Framework Class Library.