Red Beach Plus Size Maxi Women Wine AMZ Floral Sleeveless Bohemian Dress 1 PLUS Pxqp0T
Printing Pattern3 Stylish Coolred Tube Sexy Flounced Sun Mini A Dress Women Line Coolred Tube Sun Sexy Dress Pattern3 Stylish Mini Women Line Printing Flounced A

Pattern3 Line A Coolred Sexy Tube Mini Flounced Dress Sun Printing Stylish Women t4Z4Pw

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