Build Your Own ASP.NET 2.0 Web Site Using C# & VB, Second Edition

Methods

With our dog example, we can make a particular dog do things by calling com-

mands. If I want Rayne to sit, I tell him to sit. If I want Rayne to lie down, I tell

him to lie down. In object oriented terms, I tell him what I want him to do by

calling a predefined command or method, and an action results. For example, to

make Rayne sit, we would use the following code to call his Sit method:

Visual Basic

rayne.Sit()

C#

rayne.Sit();

Given that rayne is an instance of our Dog class, we say that the Sit method is

exposed by the Dog class.

Classes

You can think of a class as a template for building as many objects of a particular

type as you like. When you create an instance of a class, you are creating an object

of that class, and the new object has all the characteristics and behaviors (prop-

erties and methods) defined by the class.

In our dog example, rayne was an instance of the Dog class, as Figure 3.6 illus-

trated. In our code, we’d create a new instance of the Dog class called rayne, as

shown below:

Visual Basic

Dim rayne As New Dog()

C#

Dog rayne = new Dog();

Constructors

Constructors are special kinds of method are that used to initialize the object.

In OOP, when we create new instances of a class, we say we’re instantiating

that class. The constructor is a method of a class that’s executed automatically

when a class is instantiated.

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Chapter 3: VB and C# Programming Basics