You're reading from Professional JavaScript for Web Developers Discover an easy-to-learn guide to upgrade your JavaScript skills

Product type Paperback

Published in Nov 2019

Publisher Wiley

ISBN-13 9781119366447

Length 1144 pages

Edition 4th Edition

Languages

JavaScript

Tools

Combine

Concepts

Web Programming

Author (1):

Matt Frisbie

View More author details

Table of Contents (37) Chapters

COVER FREE CHAPTER

FOREWORD

INTRODUCTION

1 What Is JavaScript?

2 JavaScript in HTML

3 Language Basics

4 Variables, Scope, and Memory

5 Basic Reference Types

6 Collection Reference Types

7 Iterators and Generators

8 Objects, Classes, and Object-Oriented Programming

9 Proxies and Reflect

10 Functions

11 Promises and Async Functions

12 The Browser Object Model

13 Client Detection

14 The Document Object Model

15 DOM Extensions

16 DOM Levels 2 and 3

17 Events

18 Animation and Graphics with Canvas

19 Scripting Forms

20 JavaScript APIs

21 Error Handling and Debugging

22 XML in JavaScript

23 JSON

24 Network Requests and Remote Resources

25 Client-Side Storage

26 Modules

27 Workers

28 Best Practices

A ES2018 and ES2019

B Strict Mode

C JavaScript Libraries and Frameworks

D JavaScript Tools

INDEX

END USER LICENSE AGREEMENT

INLINE CODE VERSUS EXTERNAL FILES

Although it's possible to embed JavaScript in HTML files directly, it's generally considered a best practice to include as much JavaScript as possible using external files. Keeping in mind that there are no hard and fast rules regarding this practice, the arguments for using external files are as follows:

Maintainability—JavaScript code that is sprinkled throughout various HTML pages turns code maintenance into a problem. It is much easier to have a directory for all JavaScript files so that developers can edit JavaScript code independent of the markup in which it's used.
Caching—Browsers cache all externally linked JavaScript files according to specific settings, meaning that if two pages are using the same file, the file is downloaded only once. This ultimately means faster page-load times.
Future-proof—By including JavaScript using external files, there's no need to use the XHTML or comment hacks mentioned previously...