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Professional JavaScript for Web Developers

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

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Product type Paperback
Published in Nov 2019
Publisher Wiley
ISBN-13 9781119366447
Length 1144 pages
Edition 4th Edition
Languages
Tools
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Author (1):
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Matt Frisbie Matt Frisbie
Author Profile Icon Matt Frisbie
Matt Frisbie
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Table of Contents (37) Chapters Close

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

FUNCTIONS

Functions are the core of any language because they allow the encapsulation of statements that can be run anywhere and at any time. Functions in ECMAScript are declared using the function keyword, followed by a set of arguments and then the body of the function.

The basic function syntax is as follows:

function functionName(arg0, arg1,…,argN) {
 statements
}

Here's an example:

function sayHi(name, message) {
 console.log("Hello " + name + ", " + message);
}

This function can then be called by using the function name, followed by the function arguments enclosed in parentheses (and separated by commas, if there are multiple arguments). The code to call the sayHi() function looks like this:

sayHi("Nicholas", "how are you today?");

The output of this function call is, "Hello Nicholas, how are you today?" The named arguments...

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