Wilton Paul McPeak Jeremy - Beginning JavaScript

Beginning JavaScript Fourth Edition

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ISBN: 978-0-470-52593-7

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In memory of my mum, June Wilton, who in 2006 lost her brave battle against cancer. She was always very proud of me and my books and showed my books to anyone and everyone she happened to meet however briefly and whether they wanted to see them or not! Shes very much missed. Paul Wilton

To my family: Starla, Hayden, and Evan (whom we havent yet met in person). To my parents: Jerry and Judy. Thank you all for your love and support. Jeremy McPeak

About the Authors

Paul Wilton started as a Visual Basic applications programmer at the Ministry of Defense in the UK and then found himself pulled into the Net. Having joined an Internet development company, he spent three years helping create Internet solutions. Hes now running his own successful and rapidly growing company developing online holiday property reservation systems.

Jeremy McPeak is a self-taught programmer who began his career by tinkering with web sites in 1998. He is the co-author of Professional Ajax, 2nd Edition (Wiley 2007) and several online articles covering topics such as XSLT, ASP.NET WebForms, and C#. He is currently employed in an energy-based company building in-house conventional and web applications.

Jeremy can be reached through his web site www.wdonline.com .

Credits

Acquisitions Editor

Scott Meyers

Project Editor

Maureen Spears

Technical Editor

David M. Karr

Production Editor

Rebecca Anderson

Copy Editor

C.M. Jones

Editorial Director

Robyn B. Siesky

Editorial Manager

Mary Beth Wakefield

Marketing Manager

David Mayhew

Production Manager

Tim Tate

Vice President and Executive Group Publisher

Richard Swadley

Vice President and Executive Publisher

Barry Pruett

Associate Publisher

Jim Minatel

Project Coordinator, Cover

Lindsay Stanford

Compositor

Craig Johnson, Happenstance Type-O-Rama

Proofreader

Kathryn Duggan

Indexer

J & J Indexing

Cover Image

Photographers Choice/Punchstock

Acknowledgments

First, a big thank you to my partner Beci, who, now that the books finished, will get to see me for more than 10 minutes a week.

Id also like to say a very big thank you to Maureen Spears, who has worked very efficiently on getting this book into print.

Thanks also to Jim Minatel for making this book happen.

Many thanks to everyone whos supported and encouraged me over my many years of writing books. Your help will always be remembered.

Finally, pats and treats to my German Shepherd Dog, Katie, who does an excellent job of warding off disturbances from door-to-door salespeople.

Paul Wilton

First and foremost, a huge thank you to my wife for putting up with my late nights.

Just as huge thanks go to the people at Wiley Publishing: Jim Minatel and Scott Meyers for making this happen; Maureen Spears who was absolutely wonderful to work with in getting this book into its final, printed form; and David M. Karr for keeping me honest.

Lastly, thank you Nicholas C. Zakas, author of Professional JavaScript, 2nd Edition (Wiley 2009) and co-author of Professional Ajax, 2nd Edition (Wiley 2007), for getting me into this business.

Jeremy McPeak

Introduction

JavaScript is a scripting language that enables you to enhance static web applications by providing dynamic, personalized, and interactive content. This improves the experience of visitors to your site and makes it more likely that they will visit again. You must have seen the flashy drop-down menus, moving text, and changing content that are now widespread on web sites they are enabled through JavaScript. Supported by all the major browsers, JavaScript is the language of choice on the Web. It can even be used outside web applications to automate administrative tasks, for example.

This book aims to teach you all you need to know to start experimenting with JavaScript: what it is, how it works, and what you can do with it. Starting from the basic syntax, youll move on to learn how to create powerful web applications. Dont worry if youve never programmed before this book will teach you all you need to know, step by step. Youll find that JavaScript can be a great introduction to the world of programming: with the knowledge and understanding that youll gain from this book, youll be able to move on to learn newer and more advanced technologies in the world of computing.