Cocktail 3 Printed Dress Sexy Swing Printing Sling Striped Digital Women Coolred Sleeveless xaqO08Pn1
Elastic Casual Drawstring Womens Lace Bodycon Black Dress Waist Knitted Cromoncent Knitted Drawstring Womens Waist Lace Casual Black Elastic Bodycon Cromoncent Dress

Bodycon Dress Womens Elastic Casual Lace Cromoncent Drawstring Waist Black Knitted f67Ow08

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