1920s Dress Fringe Gatsby Sequin Flapper Long Inspired Vintage Vijiv Embellished Blue O6qdPwT
Big Occasion Blue OMZIN Special Dresses Big OMZIN Girls OMZIN Girls Dresses OMZIN Big Special Occasion Big Blue

Special OMZIN Big Dresses Occasion Girls OMZIN Big Blue qrfwErI

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