in Made XSmall Pattern USA Dress Sleeveless Women Calison Summer s nZwqwH0F
Bodysuit Top Stretch Black Bardot Womens Leotard Shoulder Plain Sleeve Ladies Long Off Bardot Off Bodysuit Stretch Leotard Shoulder Womens Top Ladies Long Black Plain Sleeve

Womens Ladies Black Plain Sleeve Stretch Off Shoulder Top Leotard Bardot Long Bodysuit Z1UrWq1Bnd

A constructor parameter decorator that marks a dependency as optional.

See also

Description

The DI framework provides null if the dependency is not found. For example, the following code allows the possibility of a null result:

class Engine {} @ Injectable() class Car { constructor(@ Optional() public engine: Engine) {} } const injector = ReflectiveInjector.resolveAndCreate([Car]); expect(injector.get(Car).engine).toBeNull();
      
      class Engine {}

@Injectable()
class Car {
  constructor(@Optional() public engine: Engine) {}
}

const injector = ReflectiveInjector.resolveAndCreate([Car]);
expect(injector.get(Car).engine).toBeNull();
    

Options