Shoulder Dress Cocktail Sleeve Long Women Knit Wrapped Coolred chest Khaki Off qPYaC
Dresses Homecoming Bridesmaid Lace Chiffon Strapless Maroon Women Long s ANTS s ANTS Bridesmaid Long Maroon Dresses Lace Homecoming Strapless Women Chiffon

Bridesmaid Chiffon s Homecoming Women Long ANTS Strapless Dresses Lace Maroon tXqUcPw

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