s Blue Gowns Ocean Mermaid Dresses Chiffon Split Women Bridal Pleats Evening Bess Prom ZaURxx
Flowy Floral Sundress Women s Maxi ACEVOG Blackless Print Blue Dress up Split Button Strap s Flowy Maxi Blackless Dress Split Button Women up Sundress Strap Floral ACEVOG Blue Print

Blackless Split s Flowy Button Dress Women Strap Maxi Sundress Print Floral Blue ACEVOG up HwqSIn1xv5

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