Ruffles Bridesmaid Mother Chiffon Sleeves Dress Evening Long ASBridal Cap Mint Womens ptAwT44
Casual Black Overall Women Cromoncent Chiffon Swing Adjustable Pleated Dress Strap Cromoncent Overall Chiffon Swing Casual Women Adjustable Dress Pleated Black Strap

Dress Cromoncent Chiffon Pleated Women Black Adjustable Overall Casual Swing Strap 8O8Srqw

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