Table Of ContentObject-Oriented JavaScript
Create scalable, reusable high-quality JavaScript
applications, and libraries
Stoyan Stefanov
BIRMINGHAM - MUMBAI
Object-Oriented JavaScript
Create scalable, reusable high-quality JavaScript applications,
and libraries
Copyright © 2008 Packt Publishing
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First published: July 2008
Production Reference: 1160708
Published by Packt Publishing Ltd.
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Olton
Birmingham, B27 6PA, UK.
ISBN 978-1-847194-14-5
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Cover Image by Nilesh Mohite (nilpreet2000@yahoo.co.in)
Credits
Author Editorial Team Leader
Stoyan Stefanov Akshara Aware
Reviewers Project Manager
Dan Wellman Abhijeet Deobhakta
Douglas Crockford
Gamaiel Zavala Project Coordinator
Jayme Cousins Patricia Weir
Julie London
Nicolas Zakas Indexer
Nicole Sullivan Monica Ajmera
Philip Tellis
Ross Harmes Proofreader
Tenni Theurer Dirk Manuel
Wayne Shea
Yavor Paunov Production Coordinator
Rajni Thorat
Senior Acquisition Editor
Douglas Paterson Cover Designer
Rajni Thorat
Development Editor
Nikhil Bangera
Technical Editor
Gagandeep Singh
About the Author
Stoyan Stefanov is a Yahoo! web developer, Zend Certified Engineer, and book
author. He talks regularly about JavaScript, PHP, and other web development topics
at conferences and on his blog at www.phpied.com, and also runs a number of other
sites, including JSPatterns.com—a site dedicated to exploring JavaScript patterns.
Stoyan is the engineering lead of Yahoo!'s performance optimization tool YSlow, and
contributes to other open-source projects such as Firebug and PEAR.
A "citizen of the world", Stoyan was born and raised in Bulgaria, but is also a
Canadian citizen, and is currently residing in Los Angeles, California. In his rare
offline moments, he enjoys playing the guitar and going to the Santa Monica beaches
and pools with his family.
About the Reviewers
Dan Wellman lives with his wife and three children in his home town of
Southampton on the south coast of England. By day his mild-mannered alter-ego
works for a small yet accomplished e-commerce production agency. By night he battles
the forces of darkness and fights for truth, justice, and less intrusive JavaScript.
He has been writing computer-related articles, tutorials, and reviews for around five
years and is rarely very far from a keyboard of some description.
Douglas Crockford is a product of the US public education system. A registered
voter, he owns his own car. He is the world's foremost living authority on JavaScript.
He is the author of JavaScript: The Good Parts. He has developed office automation
systems. He did research in games and music at Atari. He was Director of
Technology at Lucasfilm. He was Director of New Media at Paramount.
He was the founder and CEO of Electric Communities/Communities.com. He was
founder and CTO of State Software, where he discovered JSON, the data interchange
standard. He is now an architect at Yahoo!
Gamaiel Zavala is a frontend engineer at Yahoo! in Santa Monica, California.
He enjoys writing all types of code and strives to understand the big picture, from
protocols and packets to the wide gamut of technologies delivering user experience
to the front end. Aside from the geeky stuff, he is enjoying a new family with his
lovely wife and baby boy.
Jayme Cousins started creating commercial websites once released from
University with a degree in Geography. His projects include marketing
super-niche spatial analysis software, preparing online content overnight for his
city's newspaper, printing road names on maps, painting houses, and teaching
College tech courses to adults. He currently lives behind a keypad in London,
Canada with his wife Heather and newborn son Alan. Jayme previously reviewed
Learning Mambo from Packt Publishing. He enjoys matching technology with
real-world applications for real-world people and often feels that his primary role is
that of a translator of technobabble for entrepreneurs.
Jayme now provides web development, consulting, and technical training through
his business, In House Logic (www.inhouselogic.com).
Julie London is a software engineer with over eight years of experience in building
enterprise-level web applications. A Flash developer for many years, she now
concentrates on other client-side technologies including CSS, JavaScript, and XSL. She
currently lives in Los Angeles where she works as a frontend engineer for Yahoo!
Nicholas C. Zakas is principal frontend engineer for the Yahoo! front page, a
contributor to YUI, and JavaScript teacher at Yahoo! He is the author of two books,
Professional JavaScript for Web Developers and Professional Ajax, as well as over a dozen
online articles on JavaScript.
Nicholas began his career as webmaster of a small software company, transitioning
into a user interface designer and prototyper before moving fully into software
engineering. He moved to Silicon Valley from Massachusetts in 2006 to join Yahoo!
Nicholas can be contacted through his website at www.nczonline.net.
Nicole Sullivan is a CSS performance guru living in California. She began her
professional career in 2000, when her future husband (then a W3C employee) told
her that if her website didn't validate he wouldn't be able to sleep at night. She
thought she'd better figure out what this ‘validator' thing was all about, and a love
for standards was born.
She began building Section 508 compliant, accessible websites. As her appreciation
for performance and large-scale sites grew, she went on to work in the online
marketing business, building CSS framework solutions for many well-known
European and world-wide brands, such as SFR, Club Med, SNCF, La Poste, FNAC,
Accor Hotels, and Renault.
Nicole now works for Yahoo! in the Exceptional Performance group. Her role
involves researching and evangelizing performance best practices and building tools
like YSlow that help other F2E's create better sites. She writes about standards, her
dog, and her obsession with object oriented CSS at www.stubbornella.org.
Philip Tellis is a lazy geek working with Yahoo! He likes letting the computer do
his work for him, and if it can't, he'll just reprogram it.
When he isn't hacking code, Philip rides his bike around Silicon Valley, and tries his
hand at food hacking, but not at the same time.
Ross Harmes works as a frontend engineer for Flickr in San Francisco, California.
He's also an author of the book Pro JavaScript Design Patterns. Some of his technical
writings and online projects, such as the YUI Bundle for TextMate, can be found at
www.techfoolery.com.
Tenni Theurer joined Yahoo! in early 2006 as a technical evangelist in Yahoo!'s
Exceptional Performance group. She then took the reins as manager and grew the
engineering team to lead the global effort in making Yahoo! products faster and
accelerating the user experience worldwide. Tenni is currently a Sr. Product Manager
in Yahoo!'s Search Distribution group. Tenni has spoken at several conferences
including Web 2.0 Expo, Ajax Experience, Rich Web Experience, AJAXWorld,
BlogHer, WITI, and CSDN-DrDobbs. She is a featured guest blogger on Yahoo!
Developer Network and Yahoo! User Interface Blog. Prior to Yahoo!, Tenni worked
in IBM's Pervasive Computing group on enterprise mobile solutions where she
worked directly with high profile customers on large-scale deployments.
Wayne Shea is a software engineer at Yahoo!. His projects at Yahoo! include
research on improving mobile web performances and developing scalable
high-performance web services. Before joining Yahoo!, he had been busy
creating mobile web browsers for cell phones at Openwave and Access.
Yavor Paunov is a product of the joined efforts of the Computer Science
departments of the Technical University, Sofia, Bulgaria, and Concordia
University in Montreal, Canada. His experience spans from two-person startups
to multi-national companies. Outside work, Yavor's habits include listening to live
music and extended walks with his charming shoe-eating cocker spaniel.
Table of Contents
Preface 1
Chapter 1: Introduction 9
A Bit of History 10
The Winds of Change 11
The Present 11
The Future 12
Object-Oriented Programming 12
Objects 13
Classes 13
Encapsulation 14
Aggregation 15
Inheritance 15
Polymorphism 16
OOP Summary 16
Setting up Your Training Environment 17
Getting the Tools You Need 17
Using the Firebug Console 18
Summary 20
Chapter 2: Primitive Data Types, Arrays, Loops,
and Conditions 21
Variables 21
Variables are Case Sensitive 22
Operators 23
Primitive Data Types 26
Finding out the Value Type —the typeof Operator 27
Numbers 27
Octal and Hexadecimal Numbers 28
Exponent Literals 29
