JavaScript For Kids For Dummies E-Book

Chris Minnick

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 306

Veröffentlichungsjahr: 2015

Beschreibung

Have big dreams? Kick start them with JavaScript! If we've learned one thing from the Millennial generation, it's that no one is too young to make history online. JavaScript For Kids For Dummies introduces pre-teens and early teens alike to the world of JavaScript, which is an integral programming language that drives the functionality of websites and apps. This informative, yet engaging text guides you through the basics of coding with JavaScript, and is an essential resource if you want to expand your technology skills while following easy, step-by-step instructions. Through small, goal-oriented projects, you learn key coding concepts, while actually creating apps, games, and more. This hands-on experience, coupled with the presentation of ideas in a simple style, allows you to both learn and retain JavaScript fundamentals. JavaScript has been heralded as 'the programming language of the web,' and many kids are interested in learning how to use it; however, most schools don't offer coding classes at this level, and most families can't afford the high cost of coding classes through a summer camp. But this can't stop you from developing your JavaScript coding skills! This fun text is all you need to get started on your JavaScript journey. * Explore the basics of JavaScript through the creation of a calculator app * Deepen your understanding of HTML, arrays, and variables by building a grocery shopping app * Learn conditional logic through the development of a choose your own adventure game * Discover loops and strings by creating a lemonade stand app and MadLibs-style game JavaScript For Kids For Dummies brings pre-teens and early teens into the world of coding by teaching them one of the key Web design languages.

Leseprobe

JavaScript® For Kids For Dummies®

Published by: John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030-5774, www.wiley.com

Copyright © 2015 by John Wiley & Sons, Inc., Hoboken, New Jersey

Published simultaneously in Canada

No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without the prior written permission of the Publisher. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, [phone], fax [phone], or online at http://www.wiley.com/go/permissions.

Trademarks: Wiley, For Dummies, the Dummies Man logo, Dummies.com, Making Everything Easier, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc., and may not be used without written permission. JavaScript is a registered trademark of Oracle, Inc. All other trademarks are the property of their respective owners. John Wiley & Sons, Inc., is not associated with any product or vendor mentioned in this book.

LIMIT OF LIABILITY/DISCLAIMER OF WARRANTY: WHILE THE PUBLISHER AND AUTHOR HAVE USED THEIR BEST EFFORTS IN PREPARING THIS BOOK, THEY MAKE NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY OR COMPLETENESS OF THE CONTENTS OF THIS BOOK AND SPECIFICALLY DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. NO WARRANTY MAY BE CREATED OR EXTENDED BY SALES REPRESENTATIVES OR WRITTEN SALES MATERIALS. THE ADVICE AND STRATEGIES CONTAINED HEREIN MAY NOT BE SUITABLE FOR YOUR SITUATION. YOU SHOULD CONSULT WITH A PROFESSIONAL WHERE APPROPRIATE. NEITHER THE PUBLISHER NOR THE AUTHOR SHALL BE LIABLE FOR DAMAGES ARISING HEREFROM.

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Wiley publishes in a variety of print and electronic formats and by print-on-demand. Some material included with standard print versions of this book may not be included in e-books or in print-on-demand. If this book refers to media such as a CD or DVD that is not included in the version you purchased, you may download this material at http://booksupport.wiley.com. For more information about Wiley products, visit www.wiley.com.

Library of Congress Control Number: 2015945282

ISBN 978-1-119-11986-9 (pbk); ISBN 978-1-119-11989-0 (ebk); ISBN 978-1-119-11988-3

JavaScript For Kids For Dummies

Visit www.dummies.com/cheatsheet/javascriptforkids to view this book's cheat sheet.

Table of Contents

Cover

Introduction

About This Book

Foolish Assumptions

Icons Used In This Book

Beyond the Book

Where to Go from Here

Part I: What Is JavaScript? Alert! JavaScript Is Awesome!

Chapter 1: Programming the Web

What Is Programming?

Talking to Computers

Choosing a Language

What Is JavaScript?

Get Your Browser Ready

Opening the Web Developer Tools

Introducing the JavaScript Console

Running Your First JavaScript Commands

Having Fun with Math

Chapter 2: Understanding Syntax

Saying Precisely What You Mean

Making a Statement

Following the Rules

Chapter 3: Giving and Receiving Data

Mastering Variables

Understanding Data Types

Prompting the User for Input

Responding to Input

Combining Input and Output

Chapter 4: Fiddling with Web Applications

Introducing JSFiddle

Creating a JSFiddle Account

Sharing Your Fiddle

Saving Your App

Part II: Animating the Web

Chapter 5: JavaScript and HTML

Writing HTML

Knowing Your HTML Elements

Adding Attributes to Elements

Changing HTML with JavaScript

Chapter 6: JavaScript and CSS

Meet Douglas the JavaScript Robot

CSS Basics

CSS Properties Give You Style

Customize Your Own JavaScript Robot!

Chapter 7: Building an Animated Robot

Changing CSS with JavaScript

Make Douglas Dance!

Adding a second animation function

Part III: Getting Operations

Chapter 8: Building Your Dream Car with Operands

Knowing Your Operands

Working with Objects

Configuring Your Dream Car

Chapter 9: Putting It Together with Operators

Introducing the Super-Calculator

Super-Calculator Tricks

Chapter 10: Creating Your Own JavaScript Word Game

Creating a Variable Story

Creating the Word Replacement Game

Part IV: Arrays and Functions

Chapter 11: Creating and Changing Arrays

What Are Arrays?

Creating and Accessing Arrays

Changing Array Element Values

Working with Array Methods

Learning the Ways of Arrays

Chapter 12: Making It Functional

Understanding Functions

Knowing What Functions Are Made Of

Building Function Junction

Chapter 13: Creating a Wish List Program

Introducing the Wish List Program

Forking the Code

Writing the HTML

Writing the JavaScript Code

Part V: Freedom of Choice

Chapter 14: Making Decisions with the If…Else Statement

Boolean Logic

Introducing if…else Statements

Combining Comparisons with Logical Operators

Freshening Up the JavaScript Pizzeria

Chapter 15: Doing Different Things with Switch

Writing a Switch

Building the Activity-of-the-Day Calendar

Chapter 16: Choose Your Own Adventure

Planning the Story

Playing the Game

Forking the Code

Tiptoeing through the HTML and CSS

Writing the Martian Rescue! JavaScript

Part VI: Loops

Chapter 17: What’s This Loop For?

Introducing the for Loop

Random Weather Forecasting

Chapter 18: Using While Loops

Writing a while Loop

Coding the Lunch Game

Moving to Your Own Website

Chapter 19: Building a Lemonade Stand

Playing the Game

A Lesson in Business

Building the Game

Improving the Lemonade Game

About the Authors

Cheat Sheet

Advertisement Page

Connect with Dummies

End User License Agreement

Guide

Cover

Table of Contents

Begin Reading

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Introduction

JavaScript For Kids For Dummies is an introduction to the basics of JavaScript coding. In each chapter, we walk you step-by-step through creating JavaScript programs for the web. Designed for kids of all ages, with no coding experience, we strive to introduce this technical topic in a fun, engaging, and interactive way.

JavaScript is the most widely used programming language in the world today. That’s why we think you’ve made a great decision by beginning your journey into the world of coding by picking up this book.

JavaScript is fun and easy to learn! With some determination and imagination, you’ll be on your way to creating your very own JavaScript programs in no time!

Just as the only way to Carnegie Hall is to practice, practice, practice, the only way to become a better programmer is to code, code, code!

About This Book

We seek to “de-code” the language of JavaScript for you and give you an understanding of the concepts. With the ability to move at your own pace, JavaScript For Kids For Dummies will get you up to speed. In this book, you learn how to create fun games and programs. We even show you how to customize and build your own versions of the games that you can post to the web and share with your friends!

Whether you know a little JavaScript or you’ve never seen it before, this book shows you how to write JavaScript the right way.

Topics covered in this book include the following:

The basic structures of JavaScript programs

JavaScript expressions and operators

Structuring your programs with functions

Writing loops

Working with JavaScript, HTML5, and CSS3

Making choices with

if…else

statements

Learning JavaScript isn’t only about learning how to write the language. It’s also about accessing the tools and the community that has been built around the language. JavaScript programmers have refined the tools and techniques used to write JavaScript over the language’s long and exciting history. Throughout this book, we mention important techniques and tools for testing, documenting, and writing better code!

To make this book easier to read, you’ll want to keep in mind a few tips. First, all JavaScript code and all HTML and CSS markup appears in monospaced type like this:

document.write("Hi!");

The margins on a book page don’t have the same room as your monitor likely does, so long lines of HTML, CSS, and JavaScript may break across multiple lines. Remember that your computer sees such lines as single lines of HTML, CSS, or JavaScript. We indicate that everything should be on one line by breaking it at a punctuation character or space and then indenting any overage, like so:

document.getElementById("thisIsAnElementInTheDocument").addEventListener("click",doSomething,false);

HTML and CSS don’t care very much about whether you use uppercase or lowercase letters or a combination of the two. But, JavaScript cares a lot! In order to make sure that you get the correct results from the code examples in the book, always stick to the same capitalizations that we use.

Foolish Assumptions

You don’t need to be a “programming ninja” or a “hacker” to understand programming. You don’t need to understand how the guts of your computer work. You don’t even need to know how to count in binary.

However, we do need to make a couple of assumptions about you. We assume that you can turn your computer on, that you know how to use a mouse and a keyboard, and that you have a working Internet connection and web browser. If you already know something about how to make web pages (it doesn’t take much!), you’ll have a jumpstart on the material.

The other things you need to know to write and run JavaScript code are details we cover in this book, and the one thing you’ll find to be true is that programming requires attention to details.

Icons Used In This Book

Here’s a list of the icons we use in this book to flag text and information that’s especially noteworthy.

This icon highlights technical details that you may or may not find interesting. Feel free to skip this information, but if you’re the techie type, you might enjoy reading it.

This icon highlights helpful tips that show you easy ways or shortcuts that will save you time or effort.

Whenever you see this icon, pay close attention. You won’t want to forget the information you’re about to read — or, in some cases, we’ll remind you about something that you’ve already learned that you may have forgotten.

Be careful. This icon warns you of pitfalls to avoid.

Beyond the Book

We’ve put together a lot of extra content that you won’t find in this book. Go online to find the following:

Cheat Sheet:

An online Cheat Sheet is available at

www.dummies.com/cheatsheet/javascriptforkids

. Here, you find information on converting CSS property names to JavaScript; a list of common web browser events that JavaScript can respond to; and a list of words that can’t be used as JavaScript variables, functions, methods, loop labels, or object names.

Web Extras:

Online articles covering additional topics are available at

www.dummies.com/extras/javascriptforkids

. In these articles, we cover things like HTML5 form input tricks, how to name JavaScript variables, JavaScript troubleshooting tips, and more.

Where to Go from Here

Coding with JavaScript is fun, and when you get a little knowledge under your belt, the world of interactive web applications is your oyster! So buckle up! We hope you enjoy the book and our occasional pearls of wisdom.

If you want to show us changes and improvements you make to our games, or programs you come up with on your own, you can do so on Facebook (www.facebook.com/watzthisco), Twitter (www.twitter.com/watzthisco), or via email at [email protected]. We’re excited to see what you come up with!

Part I

What Is JavaScript? Alert! JavaScript Is Awesome!

In this part …

Programming the Web

Understanding Syntax

Giving and Receiving Data

Fiddling with Web Applications

For Dummies can help you get started with lots of subjects. Visit www.dummies.com to learn more and do more with For Dummies!

Chapter 1

Programming the Web

JavaScript is a powerful language that’s easy to learn! In this chapter, we explain the basics of programming, tell you what JavaScript is, and get you started with writing your first JavaScript commands.

One of the most important parts of starting any new project is to make sure you have your workshop stocked with all the correct tools. In this chapter, you install and configure all the programs you need and start experimenting with some real JavaScript programs!

What Is Programming?

A computer program is a series of instructions that can be understood and followed by a computer. Computer programming, also known as coding, is what we call it when we write these instructions. Computers can’t do things on their own. They need a computer program to tell them what to do. Computer programmers write code to make computers do all sort of things.