What it does
A parameter decorator that specifies a dependency.
How to use
@Injectable() class Car { constructor(@Inject("MyEngine") public engine:Engine) {} }
Description
For more details, see the Dependency Injection Guide.
Example
class Engine {}
@Injectable()
class Car {
constructor(@Inject('MyEngine') public engine: Engine) {}
}
const injector =
ReflectiveInjector.resolveAndCreate([{provide: 'MyEngine', useClass: Engine}, Car]);
expect(injector.get(Car).engine instanceof Engine).toBe(true);
When @Inject()
is not present, Injector
will use the type annotation of the
parameter.
Example
class Engine {}
@Injectable()
class Car {
constructor(public engine: Engine) {
} // same as constructor(@Inject(Engine) engine:Engine)
}
const injector = ReflectiveInjector.resolveAndCreate([Engine, Car]);
expect(injector.get(Car).engine instanceof Engine).toBe(true);
exported from core/index defined in core/src/di/metadata.ts