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Injectable

decorator stable

npm Package @angular/core
Module import { Injectable } from '@angular/core';
Source core/src/di/metadata.ts

A marker metadata that marks a class as available to Injector for creation.

Metadata Overview

@Injectable({ 
})

How To Use

@Injectable()
class Car {}

Description

For more details, see the "Dependency Injection Guide".

Example

@Injectable()
class UsefulService {
}

@Injectable()
class NeedsService {
  constructor(public service: UsefulService) {}
}

const injector = ReflectiveInjector.resolveAndCreate([NeedsService, UsefulService]);
expect(injector.get(NeedsService).service instanceof UsefulService).toBe(true);
Injector

will throw an error when trying to instantiate a class that does not have @Injectable marker, as shown in the example below.

class UsefulService {}

class NeedsService {
  constructor(public service: UsefulService) {}
}

expect(() => ReflectiveInjector.resolveAndCreate([NeedsService, UsefulService])).toThrow();

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Licensed under the Creative Commons Attribution License 4.0.
https://angular.io/api/core/Injectable