Book Image

Learning jQuery 3 - Fifth Edition

By : Jonathan Chaffer, Karl Swedberg
Book Image

Learning jQuery 3 - Fifth Edition

By: Jonathan Chaffer, Karl Swedberg

Overview of this book

If you are a web developer and want to create web applications that look good, are efficient, have rich user interfaces, and integrate seamlessly with any backend using AJAX, then this book is the ideal match for you. We’ll show you how you can integrate jQuery 3.0 into your web pages, avoid complex JavaScript code, create brilliant animation effects for your web applications, and create a flawless app. We start by configuring and customising the jQuery environment, and getting hands-on with DOM manipulation. Next, we’ll explore event handling advanced animations, creating optimised user interfaces, and building useful third-party plugins. Also, we'll learn how to integrate jQuery with your favourite back-end framework. Moving on, we’ll learn how the ECMAScript 6 features affect your web development process with jQuery. we’ll discover how to use the newly introduced JavaScript promises and the new animation API in jQuery 3.0 in great detail, along with sample code and examples. By the end of the book, you will be able to successfully create a fully featured and efficient single page web application and leverage all the new features of jQuery 3.0 effectively.
Table of Contents (23 chapters)
Title Page
About the Authors
About the Reviewer
Customer Feedback

Iterating over jQuery objects

New in jQuery 3 is the ability to iterate over jQuery objects using a for...of loop. This by itself isn't a big deal. For one thing, it's rare that we need to explicitly iterate over jQuery objects, especially when the same result is possible by using implicit iteration in jQuery functions. But sometimes, explicit iteration can't be avoided. For example, imaging you need to reduce an array of elements (a jQuery object) to an array of string values. The each() function is a tool of choice here:

const eachText = [];

  .each((i, td) => {
    if (td.textContent.startsWith('H')) {

console.log('each', eachText);
 // ["Hamlet", "Henry IV, Part I", "History", "Henry V", "History"]

Listing 2.17

We start off with an array of <td> elements, the result of our $('td') selector. We then reduce it to an array of strings by passing the each() function a callback that pushes each string that starts with "H" onto...