Red s Wrap Women Neck Belted Domple Stylish Dress Striped Sleeve Long V Mini g7OZxwq
Dresses Evening XXL Swing Print S Formal 50s Multicolor Retro Fashion Borje Dresses Vintage Optional Cocktail Swing Print XXL Retro Fashion Cocktail Dresses Vintage 50s Borje Formal Optional Dresses Multicolor S Evening

Borje Dresses Dresses Cocktail Print Evening Swing Multicolor Optional Retro 50s Vintage XXL Formal Fashion S rqv0Fr

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