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

Heads-up when copying by reference

The fact that objects (including functions and arrays) are copied by reference could sometimes lead to results you don't expect.

Let's create two constructor functions and add properties to the prototype of the first one:

    > function Papa() {} 
    >function Wee() {} 
    > = 'Bear';  
    >Papa.prototype.owns = ["porridge", "chair", "bed"]; 

Now, let's have Wee inherit from Papa (either extend() or extend2() will do):

    >extend2(Wee, Papa); 

Using extend2(), the Wee function's prototype inherited the properties of Papa.prototype as its own:


The name property is primitive, so a new copy of it is created. The owns property is an array object, so it's copied by reference:

    ["porridge", "chair", "bed"]