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

THE <NOSCRIPT> ELEMENT

Of particular concern to early browsers was the graceful degradation of pages when the browser didn't support JavaScript. To that end, the <noscript> element was created to provide alternate content for browsers without JavaScript. Although effectively 100% of browsers now support JavaScript, this element is still useful for browsers that explicitly disable JavaScript.

The <noscript> element can contain any HTML elements, aside from <script>, that can be included in the document <body>. Any content contained in a <noscript> element will be displayed under only the following two circumstances:

The browser doesn't support scripting.
The browser's scripting support is turned off.

If either of these conditions is met, then the content inside the <noscript> element is rendered. In all other cases, the browser does not render the content of <noscript>.

Here is a simple example: