ActionScript for Flash MX: The Definitive Guide, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

Further ActionScript Concepts

|

15

Here we see the variable message:

var message = "Hi there, Flash!";

If we like, we can combine the variable expression message with the literal expres-

sion “ How are you?” as follows:

message + " How are you?"

which becomes “Hi there, Flash! How are you?” when the program runs. You’ll fre-

quently see complex expressions that include shorter expressions when working with

arithmetic, such as:

(2 + 3) * (4 / 2.5) - 1

It’s important to be exposed to expressions early in your programming career,

because the term “expression” is often used in descriptions of programming con-

cepts. For example, I might write, “To assign a value to a variable, type the name of

the variable, then an equals sign followed by any expression.”

Two Vital Statement Types: Conditionals and Loops

In nearly all programs, we’ll use conditionals to add logic to our programs and loops

to perform repetitive tasks.

Making choices using conditionals

One of the really rewarding aspects of Flash programming is making your movies

smart. Here’s what I mean by smart: Suppose a girl named Wendy doesn’t like get-

ting her clothes wet. Before Wendy leaves her house every morning, she looks out

the window to check the weather, and if it’s raining, she brings an umbrella.

Wendy’s smart. She uses basic