Book Image

Mastering JavaScript Object-Oriented Programming

Book Image

Mastering JavaScript Object-Oriented Programming

Overview of this book

ECMAScript 6 introduces several new Object-Oriented features that drastically change the way developers structure their projects. Web developers now have some advanced OOP functionality at their disposal to build large-scale applications in JavaScript. With this book, we'll provide you with a comprehensive overview of OOP principles in JavaScript and how they can be implemented to build sophisticated web applications. Kicking off with a subtle refresher on objects, we'll show you how easy it is to define objects with the new ES6 classes. From there, we'll fly you through some essential OOP principles, forming a base for you to get hands-on with encapsulation. You'll get to work with the different methods of inheritance and we'll show you how to avoid using inheritance with Duck Typing. From there, we'll move on to some advanced patterns for object creation and you'll get a strong idea of how to use interesting patterns to present data to users and to bind data. We'll use the famous promises to work with asynchronous processes and will give you some tips on how to organize your code effectively. You'll find out how to create robust code using SOLID principles and finally, we'll show you how to clearly define the goals of your application architecture to get better, smarter, and more effective coding. This book is your one-way ticket to becoming a JavaScript Jedi who can be counted on to deliver flexible and maintainable code.
Table of Contents (18 chapters)
Mastering JavaScript Object-Oriented Programming
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface

Objects and prototypes


Until now, we have seen two ways to create objects in JavaScript. The first and simplest approach is based on the literal notation:

var person = {name: "John", surname: "Smith"}; 

The second and more flexible approach is based on a constructor function:

function Person(name, surname) { 
  this.name = name; 
  this.surname = surname; 
} 
 
var person = new Person("John", "Smith"); 

There is no difference between the resulting objects of both approaches. Our feeling in both cases is that we have created two new objects from scratch. Actually, it is not true. In both cases, we created a derived object—an object derived from an instance of the built-in Object() constructor. It is a constructor that allows us to create a base object of all JavaScript objects—the empty object {}. Every object created using the literal notation or a constructor inherits all properties and methods of an instance of the empty object.

We can verify it by trying to call the toString()method:

var...