Flash CS3 Documentation

Learning ActionScript 2.0 in Adobe Flash > Classes > About working with built-in classes

About working with built-in classes

In object-oriented programming (OOP), a class defines a category of object. A class describes the properties (data) and behavior (methods) for an object, much like an architectural blueprint describes the characteristics of a building. For information on classes and other object-oriented programming concepts, see the following sections:

• Object-oriented programming fundamentals
• Writing custom class files

Flash has many built-in classes that you can use in your code (see About top-level and built-in classes), which helps you easily add interactivity to your applications. To use the properties and methods defined by a built-in class, you generally first create an instance of that class (except for classes that have static members). The relationship between an instance and its class is similar to the relationship between a house and its architectural blueprints, as discussed in About top-level and built-in classes.

For more information on using classes that are built into Flash, see the following topics:

• About creating a new instance of a built-in class
• Accessing built-in object properties
• About calling built-in object methods
• About class (static) members
• Preloading class files
• Excluding classes

Flash CS3