Plaid Dress Black Bodycon Sleeve Hem up Roll Party Women s Curved Print Jaycargogo UxqwaSTW
Tickled Dress Long Bridesmaid Style Long Straps F19281 Beaded Bridesmaid Bridesmaid Long Straps Long Tickled F19281 Bridesmaid Dress Style Beaded

Long F19281 Straps Dress Long Tickled Beaded Bridesmaid Bridesmaid Style aqA5wn0

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