Floral Sleeve Spring Dress Crew Long Size Plus Women Pattern16 Coolred Neck Classics Fashionable BRqa8OEwf
Stripe Blue Slim Plaid Women Irregular Color Coolred Mid Dress Length Spell Dress Spell Color Irregular Mid Length Stripe Slim Blue Women Plaid Coolred

Coolred Plaid Color Length Mid Dress Blue Irregular Women Spell Stripe Slim 8rYrOIq

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();
    

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