Book Image

Learning jQuery - Fourth Edition - Fourth Edition

Book Image

Learning jQuery - Fourth Edition - Fourth Edition

Overview of this book

To build interesting, interactive sites, developers are turning to JavaScript libraries such as jQuery to automate common tasks and simplify complicated ones. Because many web developers have more experience with HTML and CSS than with JavaScript, the library's design lends itself to a quick start for designers with little programming experience. Experienced programmers will also be aided by its conceptual consistency. LearningjQuery - Fourth Edition is revised and updated version of jQuery. You will learn the basics of jQuery for adding interactions and animations to your pages. Even if previous attempts at writing JavaScript have left you baffled, this book will guide you past the pitfalls associated with AJAX, events, effects, and advanced JavaScript language features. Starting with an introduction to jQuery, you will first be shown how to write a functioning jQuery program in just three lines of code. Learn how to add impact to your actions through a set of simple visual effects and to create, copy, reassemble, and embellish content using jQuery's DOM modification methods. The book will take you through many detailed, real-world examples, and even equip you to extend the jQuery library itself with your own plug-ins.
Table of Contents (24 chapters)
Learning jQuery Fourth Edition
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

DOM traversal under the hood


In Chapter 2, Selecting Elements, and again at the beginning of this chapter, we looked at ways of traveling from one set of DOM elements to another by calling DOM traversal methods. Our (far from exhaustive) survey of such methods included simple ways to reach neighboring cells, such as .next() and .parent(), and more complex avenues of combining selector expressions, such as .find() and .filter(). By now, we should have a fairly strong grasp of these ways of getting from one DOM element to another step-by-step.

Each time we take one of these steps, though, jQuery takes note of our travels, laying down a trail of breadcrumbs we can follow back home if needed. A couple of the methods we briefly touched on in that chapter, .end() and .addBack(), take advantage of this record-keeping. To be able to get the most out of these methods, and in general to write efficient jQuery code, we need to understand a bit more about how the DOM traversal methods do their jobs.

jQuery...