Book Image

Object-Oriented JavaScript - Third Edition

By : Ved Antani, Stoyan STEFANOV
5 (1)
Book Image

Object-Oriented JavaScript - Third Edition

5 (1)
By: Ved Antani, Stoyan STEFANOV

Overview of this book

JavaScript is an object-oriented programming language that is used for website development. Web pages developed today currently follow a paradigm that has three clearly distinguishable parts: content (HTML), presentation (CSS), and behavior (JavaScript). JavaScript is one important pillar in this paradigm, and is responsible for the running of the web pages. This book will take your JavaScript skills to a new level of sophistication and get you prepared for your journey through professional web development. Updated for ES6, this book covers everything you will need to unleash the power of object-oriented programming in JavaScript while building professional web applications. The book begins with the basics of object-oriented programming in JavaScript and then gradually progresses to cover functions, objects, and prototypes, and how these concepts can be used to make your programs cleaner, more maintainable, faster, and compatible with other programs/libraries. By the end of the book, you will have learned how to incorporate object-oriented programming in your web development workflow to build professional JavaScript applications.
Table of Contents (25 chapters)
Object-Oriented JavaScript - Third Edition
About the Authors
About the Reviewer
Customer Feedback
Built-in Functions
Regular Expressions


Variables are used to store data; they are placeholders for concrete values. When writing programs, it's convenient to use variables instead of the actual data as it's much easier to write pi instead of 3.141592653589793; especially when it happens several times inside your program. The data stored in a variable can be changed after it initially assigned, hence the name variable. You can also use variables to store data that is unknown to you while you write the code, such as the result of a later operation.

Using a variable requires the following two steps. You will need to:

  • Declare the variable

  • Initialize it, that is, give it a value

To declare a variable, you will use the var statement like the following piece of code:

    var a; 
    var thisIsAVariable;  
    var _and_this_too;  
    var mix12three; 

For the names of the variables, you can use any combination of letters, numbers, the underscore character, and the dollar sign. However, you can't start with a...