THE
MISSING
MANUAL
®
JavaScript
David Sawyer McFarland
Beijing • Cambridge • Farnham • Köln • Sebastopol • Tokyo
Do wn lo ad f ro m Wo w! e Bo ok < ww w. wo we bo ok .c om >
JavaScript: The Missing Manual
by David Sawyer McFarland
Copyright © 2008 David Sawyer McFarland. All rights reserved.
Printed in the United States of America.
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July 2008: First Edition.
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ISBN: 978-0-596-51589-8
[LSI] [2011-05-12]
iii
Table of Contents
The Missing Credits ................................................................................... xi
Introduction................................................................................................. 1
Part One: Getting Started with JavaScript
Chapter 1: Writing Your First JavaScript Program ................................ 19
Introducing Programming ...................................................................................................................... 19
What’s a Computer Program? .......................................................................................................... 21
How to Add JavaScript to a Page ........................................................................................................... 22
External JavaScript Files .................................................................................................................... 24
Your First JavaScript Program ................................................................................................................ 26
Writing Text on a Web Page ................................................................................................................... 29
Attaching an External JavaScript File ..................................................................................................... 29
Tracking Down Errors .............................................................................................................................. 32
The Firefox JavaScript Console ........................................................................................................ 34
Displaying the Internet Explorer Error Dialog Box ........................................................................ 35
Accessing the Safari Error Console ................................................................................................. 36
Chapter 2: The Grammar of JavaScript................................................... 39
Statements ................................................................................................................................................ 39
Commands ................................................................................................................................................ 40
Types of Data ............................................................................................................................................ 40
Numbers ............................................................................................................................................. 41
Strings .................................................................................................................................................. 41
Booleans ............................................................................................................................................. 42
