Book Image

Object-Oriented JavaScript - Second Edition

Book Image

Object-Oriented JavaScript - Second Edition

Overview of this book

JavaScript is the behavior, the third pillar in today's paradigm that looks at web pages as something that consists of clearly distinguishable parts: content (HTML), presentation (CSS) and behavior (JavaScript). Using JavaScript, you can create not only web pages but also desktop widgets, browser and application extensions, and other pieces of software. It's a pretty good deal: you learn one language and then code all kinds of different applications. While there's one chapter specifically dedicated to the web browser environment including DOM, Events and AJAX tutorials, the rest is applicable to the other environments Many web developers have tried coding or adopting some bits of JavaScript, but it is time to "man up" and learn the language properly because it is the language of the browser and is, virtually, everywhere. This book starts from zero, not assuming any prior JavaScript programming knowledge and takes you through all the in-depth and exciting futures hidden behind the facade. Once listed in the "nice to have" sections of job postings, these days the knowledge of JavaScript is a deciding factor when it comes to hiring web developers. After reading this book you'll be prepared to ace your JavaScript job interview and even impress with some bits that the interviewer maybe didn't know. You should read this book if you want to be able to take your JavaScript skills to a new level of sophistication.
Table of Contents (19 chapters)
Object-Oriented JavaScript Second Edition
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface
Built-in Functions
Regular Expressions
Index

BOM


The Browser Object Model (BOM) is a collection of objects that give you access to the browser and the computer screen. These objects are accessible through the global object window.

The window object revisited

As you know already, in JavaScript there's a global object provided by the host environment. In the browser environment, this global object is accessible using window. All global variables are also accessible as properties of the window object as follows:

> window.somevar = 1;
       1
> somevar;
       1

Also, all of the core JavaScript functions (discussed in Chapter 2, Primitive Data Types, Arrays, Loops, and Conditions) are methods of the global object. Have a look at the following code snippet:

> parseInt('123a456');
       123
> window.parseInt('123a456');
       123

In addition to being a reference to the global object, the window object also serves a second purpose providing information about the browser environment. There's a window object for every frame, iframe...