Zakas - Professional JavaScript for Web Developers

Professional JavaScript for Web Developers, 2nd Edition

Published by

Wiley Publishing, Inc.

10475 Crosspoint Boulevard

Indianapolis, IN 46256

www.wiley.com

Copyright 2009 by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-0-470-22780-0

Library of Congress Cataloging-in-Publication Data

Zakas, Nicholas C.

Professional JavaScript for web developers/Nicholas C. Zakas. 2nd ed.

p. cm.

Includes index.

ISBN 978-0-470-22780-0 (paper/website)

1. Web site development. 2. JavaScript (Computer program language) I. Title.

TK5105.8885.J38Z34 2008

005.2'762 dc22

2008045552

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Dedicated to my family: mom, dad, Greg, Yiayia, and Papou. We may be few in numbers, but we are mighty! Your constant love and support have made the past couple of years possible.

About the Author

Nicholas C. Zakas has a B.S. in Computer Science from Merrimack College and an M.B.A. from Endicott College. He is the coauthor of Professional Ajax, Second Edition (Wiley, 2007) as well as dozens of online articles. Nicholas works for Yahoo! as a principal front-end engineer on Yahoo!s front page and a contributor to the Yahoo! User Interface (YUI) Library. He has worked in web development for more than eight years, during which time he has helped develop web solutions in use at some of the largest companies in the world.

Nicholas can be reached through his web site www.nczonline.net .

Credits

Acquisitions Director

Jim Minatel

Senior Development Editor

Kevin Kent

Technical Editor

Alexei Gorkov

Development Editor

Gus Miklos

Production Editor

Rebecca Coleman

Copy Editors

Foxxe Editorial Services, Candace English

Editorial Manager

Mary Beth Wakefield

Production Manager

Tim Tate

Vice President and Executive Group Publisher

Richard Swadley

Vice President and Executive Publisher

Joseph B. Wikert

Project Coordinator, Cover

Lynsey Stanford

Proofreader

Kathryn Duggan

Indexer

Jack Lewis

Acknowledgments

It takes many people to create a single book, and Id like to thank some people here for their contributions to this work.

First and foremost, thanks to everyone at Wiley for their support: Jim Minatel for once again putting his faith in me; Kevin Kent for dealing with the hectic outline rearrangements I tend to make throughout writing; and Alexei Gorkov, the best technical editor in the world, who makes sure that everything I say is 100-percent accurate.

A big thanks to everyone who provided feedback on draft chapters: David Serduke, Julian Turner, Pete Frueh, Chris Klaiber, Stoyan Stefanov, Ross Harmes, and David Golightly. Your early feedback was really helpful in making this book what it is today.

Last, thanks to Eric Miraglia for his contribution of a foreword. Eric is the reason I ended up at Yahoo!, and it has been a pleasure to work with him for the past two years.

Contents

The Element

Document Modes

The Element

Summary

Chapter 3: Language Basics

Syntax

Keywords and Reserved Words

Variables

Data Types

Operators

Statements

Functions

Summary

Chapter 4: Variables, Scope, and Memory

Primitive and Reference Values

Execution Context and Scope

Garbage Collection

Summary

Chapter 5: Reference Types

The Object Type

The Array Type

The Date Type

The RegExp Type

The Function Type

Primitive Wrapper Types

Built-in Objects

Summary

Chapter 6: Object-Oriented Programming

Creating Objects

Inheritance

Summary

Chapter 7: Anonymous Functions

Recursion

Closures

Mimicking Block Scope

Private Variables

Summary

Chapter 8: The Browser Object Model