JavaScript, A Beginner's Guide, Third Edition (Beginner's Guide (Osborne Mcgraw Hill))

512 Pages·2009·6.29 MB·English

by  John Pollock

JavaScript
A Beginner’s Guide
Third Edition
BeginNew-Tight / JavaScript: A Beginner’s Guide / John Pollock / 295-6 / Front Matter
Blind Folio: ii
About the Author
John Pollock is employed as a Web Administrator during
the day and works on Web sites and other projects during the
evening. He runs two Web sites devoted to Web development
and design—PageResource.com (www.pageresource.com)
is a development tutorial site, and JavaScript City (www
.javascriptcity.com) is a site that offers free JavaScript code
to Web developers. John holds a bachelor of arts in English
from Sam Houston State University and currently lives in New
Waverly, Texas with his wife Heather.
About the Technical Editor
Scott Duffy is an author and consultant based in Toronto,
Canada. He designs and develops Web sites for small and
medium-sized companies.
JavaScript
A Beginner’s Guide
Third Edition
John Pollock
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To my wife Heather Pollock, Bruce and Joy Anderson, and
Dr. J. D. and Linda Andrews

In memory of James D. and Livian Anderson, John William and Edith Hopkins,
Burley T. and Aline Price, and “Doc” Flores
This page intentionally left blank
Contents at a Glance
1 Introduction to JavaScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Placing JavaScript in an HTML File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3 Using Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4 Using Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
5 JavaScript Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6 Conditional Statements and Loops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
7 Event Handlers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
8 Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
9 The Document Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
10 Window Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
11 JavaScript Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
12 Math, Number, and Date Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
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viii JavaScript: A Beginner’s Guide
13 Handling Strings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
14 JavaScript and Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375
15 JavaScript and Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
16 An Introduction to Advanced Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435
A Answers to Self Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 467
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 479
Contents
ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
1 Introduction to JavaScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
What You Need to Know . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Basic HTML and CSS Knowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Basic Text Editor and Web Browser Knowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Which Version? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Remember, It’s Not Java . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Similarities to Other Languages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Beginning with JavaScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Object Based . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Client Side . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Scripting Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Putting It All Together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Online Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Try This 1-1: Use JavaScript to Write Text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
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