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

Building a provider-configured service with useFactory


One further extension of dependency injection in Angular 2 is the ability to use factories when defining your provider hierarchy. A provider factory allows you to accept input, perform arbitrary operations to configure the provider, and return that provider instance for injection.

Note

The code, links, and a live example of this are available at http://ngcookbook.herokuapp.com/0049/.

Getting ready

Begin again with the dual service and article component setup shown in Service injection aliasing with useClass and useExisting, earlier in the chapter.

How to do it...

Provider factories in Angular 2 are exactly as you might imagine they would be: functions that return a provider. The factory can be specified in a separate file and referenced with the useFactory provide option.

Begin by combining the two services into a single service, which will be configured with a method call:

[app/article.service.ts] 
 
import {Injectable} from '@angular...