Bear Bibeault - jQuery in Action

For online information and ordering of this and other Manning books, please visit www.manning.com. The publisher offers discounts on this book when ordered in quantity. For more information, please contact

Special Sales Department Manning Publications Co. 20 Baldwin Road PO Box 761 Shelter Island, NY 11964 Email: orders@manning.com

2015 by Manning Publications Co. All rights reserved.

No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by means electronic, mechanical, photocopying, or otherwise, without prior written permission of the publisher.

Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in the book, and Manning Publications was aware of a trademark claim, the designations have been printed in initial caps or all caps.

Recognizing the importance of preserving what has been written, it is Mannings policy to have the books we publish printed on acid-free paper, and we exert our best efforts to that end. Recognizing also our responsibility to conserve the resources of our planet, Manning books are printed on paper that is at least 15 percent recycled and processed without the use of elemental chlorine.

Manning Publications Co.20 Baldwin RoadPO Box 761Shelter Island, NY 11964

Development editors: Jeff Bleiel, Sean DennisTechnical development editor: Al SchererCopyeditor: Linda RecktenwaldProofreader: Melody DolabTechnical proofreader: Richard Scott-RobinsonTypesetter: Dottie MarsicoCover designer: Marija Tudor

ISBN 9781617292071

Printed in the United States of America

1 2 3 4 5 6 7 8 9 10 EBM 20 19 18 17 16 15

To Annarita, because you give balance to my life

Aurelio

Every technical book should be like this one...concise but clear, humorous but not silly, and one that answers all the questions it raises, quickly. The reader is never left wondering But what about... for more than a sentence or two.

JRoller Online Book Reviews

Thanks to the authors and their exemplary style, this comprehensive book, or operating manual as it might be called, can be taken in a front-to-back approach to learn from scratch, or as a reference for those already dabbling in jQuery and needing verification of best practices.

Matthew McCullough Denver Open Source Users Group

With its capable technical coverage, extensive use of sample code, and approachable style, this book is a valuable resource for any web developer seeking to maximize the power of JavaScript, and a must-have for anyone interested in learning jQuery.

Michael J. Ross Web Developer and Slashdot Contributor

An excellent work, a worthy successor to others in Mannings In Action series. It is highly readable and chock-full of working code. The Lab Pages are a marvelous way to explore the library, which should become an important part of every web developers arsenal. Five stars all round!

David Sills JavaLobby, DZone

I highly recommend the book for learning the fundamentals of jQuery and then serving as a good reference book as you leverage the power of jQuery more and more in your daily development.

David Hayden MVP C#, Codebetter.com

I highly recommend this book to any novice or advanced JavaScript developers who want to get serious about JavaScript and start writing optimized and elegant code without all the hassle of traditional JavaScript code authoring.

Vals Blog

The Elements of Style for JavaScript.

Joshua Heyer Trane Inc.

A decade ago, John Resig imagined a JavaScript library that would simplify the way people built web sites. Today, that library, jQuery, is used by more than 80% of all web sites that use JavaScript, according to BuiltWith.com. It would be hard to call yourself a web developer today without knowing jQuery.

On the technical side, jQuery simplifies the long-winded native method calls that browsers use and shrinks the number of lines of code that it takes to get things done. Thats why jQuerys motto is . jQuery also paves over the differences in behaviorand even some outright bugsthat exist in browsers. That simplifies both development and testing.

From the start, jQuery was designed so that it could be extended by others. The jQuery plugin model lets anyone build specialized functionality on top of what jQuery already offers. There are thousands of jQuery plugins that do everything from lightboxes to form validation. The result is that many people with only a modest amount of programming skill are able to create beautiful and functional web sites by building on the work that others have done.

Still, code alone is not what made jQuery popular. From the beginning, a strong community of helpful developers filled online forums and mailing lists to answer questions for newcomers. The insight gained from those discussions led to better documentation, training classes, and books like this one.

This book is a great way to learn jQuery. Early on, it covers a central tenet of jQuerys API, which is to select some elements on a web page and do something with them. That same pattern applies whether you are hiding, showing, animating, removing, or changing an elements appearance. The selection process uses the standard CSS selector syntax, with some jQuery enhancements that give selection even more power.

I must confess that the chapter on events is my favorite because my first major code contribution to jQuery was the rewrite of the event module in jQuery 1.7. This chapter does a great job of explaining the purpose and usefulness of events on a web page, which are the main way that you can be notified of how the user is interacting with the web page. Nearly every jQuery operation you do is started through an event of some kind.

Im also glad this book covers some topics often ignored, such as unit testing and organization of large projects. Many small projects eventually turn into large ones, and the advice in these chapters can help you to manage that growth in a way that reduces maintenance headaches.

The chapters building demo applications do a great job of showing how all the parts of jQuery fit together and demonstrate important concepts like templating that are central to all modern JavaScript frameworks and applications. Even today, I feel a bit amazed by demos like this showing its possible to build something useful with very little code.

Aurelio De Rosa has been a contributor to the jQuery community for several years and is a member of jQuerys content team that ensures jQuerys online documentation is up-to-date. His work on this latest edition of jQuery in Action gives you timely information that reflects the most recent version of the library. Aurelio has also made jQuerys online documentation better in the process of writing this book by uncovering inconsistencies and missing information. You, as a reader of this book and soon-to-be jQuery developer, are the lucky beneficiary. Go forward and,

D AVE M ETHVIN P RESIDENT , JQ UERY F OUNDATION