Chapter 5. Using Functions

When programming, you may find yourself using the same chunks of code over and over either by copying and pasting them or by rewriting the same lines of ActionScript. There is, however, a way to write ActionScript just once and then reuse it any time with a single action. You do this via functions, and the action by which you execute a function is a call or a function call. Functions are real time-savers both during development and during code maintenance because they reduce the amount of code you need to write or modify. Think of a function as a mini-program that serves a specific purpose within another application. You can use it to perform a set of specific actions, or you can feed it information and output a result or you can do both. Functions provide a powerful and versatile way to script your project.

You will create several functions that allow you to turn a Flash-TV (a simple Flash app that acts like a TV and remote control) on and off and change its channels.

In this lesson, you'll learn how to create and use functions while developing a functional remote control for a Flash-made television set.

WHAT YOU WILL LEARN

In this lesson, you will:

• Create a function

• Call a function

• Add parameters to a function

• Create a function that returns a result

• Use local variables

APPROXIMATE TIME

This lesson takes approximately 1½ hours to complete.

LESSON FILES

Starting File:

Lesson05/Assets/television1.fla

Lesson05/Assets/television2.fla

Lesson05/Assets/television3.fla

Completed Project:

television4.fla