Angular 2 Cookbook

Injecting a value as a service with useValue and OpaqueTokens

In Angular 1, there was a broad selection of service types you could use in your application. A subset of these types allowed you to inject a static value instead of a service instance, and this useful ability is continued in Angular 2.

Note

The code, links, and a live example of this are available at http://ngcookbook.herokuapp.com/3032/.

Getting ready

Begin with the following simple application:

[app/app.module.ts] import {NgModule} from '@angular/core'; import {BrowserModule} from '@angular/platform-browser'; import {RootComponent} from './root.component'; import {ArticleComponent} from './article.component'; @NgModule({ imports: [ BrowserModule ], declarations: [ RootComponent, ArticleComponent ...