Example of Angular injecting an object through dependency injection mechanism

Suppose I define an interface AppConfig and an object HERO_DI_CONFIG in app.config.ts, I want to inject the latter into the constructor of a class:

export interface AppConfig {
    apiEndpoint: string;
    title: string;
  }

import { InjectionToken } from '@angular/core';

export const APP_CONFIG = new InjectionToken<AppConfig>('app.config');

export const HERO_DI_CONFIG: AppConfig = {
  apiEndpoint: 'api.heroes.com',
  title: 'Dependency Injection'
};

Use InjectionToken to create a new token. The type parameter is AppConfig. App.config in single quotes is the description of the injection token.

Use useValue injection in NgModule:

Where you need to use this dependency, pass token APP_CONFIG to @Inject:

The final effect:

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