Book Image

Angular 2 Cookbook

By : Patrick Gillespie, Matthew Frisbie
Book Image

Angular 2 Cookbook

By: Patrick Gillespie, Matthew Frisbie

Overview of this book

Angular 2 introduces an entirely new way to build applications. It wholly embraces all the newest concepts that are built into the next generation of browsers, and it cuts away all the fat and bloat from Angular 1. This book plunges directly into the heart of all the most important Angular 2 concepts for you to conquer. In addition to covering all the Angular 2 fundamentals, such as components, forms, and services, it demonstrates how the framework embraces a range of new web technologies such as ES6 and TypeScript syntax, Promises, Observables, and Web Workers, among many others. This book covers all the most complicated Angular concepts and at the same time introduces the best practices with which to wield these powerful tools. It also covers in detail all the concepts you'll need to get you building applications faster. Oft-neglected topics such as testing and performance optimization are widely covered as well. A developer that reads through all the content in this book will have a broad and deep understanding of all the major topics in the Angular 2 universe.
Table of Contents (18 chapters)
Angular 2 Cookbook
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface

Introduction


Before you get into the meat of Angular 2 Observables, it is important to first understand the problem you are trying to solve.

A frequently encountered scenario in software is where you are expecting some entity to broadcast that something happened; let's call this an "event" (distinct from a browser event). You would like to hook into this entity and attach behavior to it whenever an event occurs. You would also like to be able to detach from this entity when you no longer care about the events it is broadcasting.

There is more nuance and additional complexity to Observables that this chapter will cover, but this concept of events underscores the fundamental pattern that is useful to you as the developer.

The Observer Pattern

The Observer Pattern isn't a library or framework. It is just a software design pattern upon which ReactiveX Observables are built. Many languages and libraries implement this pattern, and ReactiveX is just one of these implementations; however, ReactiveX...