Classes and Inheritance 靜宜大學資工系 蔡奇偉副教授 ©2011

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Class Inheritance Base Class Derived Class

Accessing the Inherited Members

All Classes Are Derived from Class object

Hiding Members of a Base Class

Base Access keyword base

Using References to a Base Class An instance of a derived class consists of an instance of the base class, plus the additional members of the derived class. A reference to the derived class points to the whole class object, including the base class part. If you have a reference to a derived class object, you can get a reference to just the base class part of the object by casting the reference to the type of the base class by using the cast operator. The cast operator is placed in front of the object reference and consists of a set of parentheses containing the name of the class being cast to.

Virtual and Override Methods

Constructor Execution

Constructor Initializers

use a different constructor from the same class

Class Access Modifiers

Inheritance Between Assemblies

Member Access Modifiers

Regions Accessing a Member

Public Member Accessibility

Private Member Accessibility

Protected Member Accessibility

Internal Member Accessibility

Protected Internal Member Accessibility

Summary of Member Access Modifiers

Abstract Members An abstract member is a function member that is designed to be overridden.

Comparing Virtual and Abstract Members

Abstract Classes

Sealed Classes

Static Classes A static class is a class where all the members are static. Static classes are used to group data and functions that are not affected by instance data. A common use of a static class might be to create a math library containing sets of mathematical methods and values.

Extension Methods