Evening Club Painting Women Backless Dresses Pattern12 Vintage Tube Waist Coolred w0YOqq
Dress Summer Strap Womens Black Color Sexy Club Bodycon Solid Spaghetti Jaycargogo Summer Black Color Jaycargogo Bodycon Club Sexy Spaghetti Solid Strap Womens Dress

Black Womens Spaghetti Club Bodycon Color Summer Solid Sexy Strap Jaycargogo Dress avwdXqq

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