V Solid Women Coolred Sling Orange1 Pockets Deep Neck Dress Maxi Beach EPaxqC
Wear Casual 12 Trendy Shirt Girls Fashion Shirt Tees T Faith Digital Leisure Tunic Tops Women Thin Printed YICHUN Fashion T 12 Girls Shirt Trendy Thin Tunic Women Tees Printed YICHUN Faith Shirt Digital Wear Leisure Tops Casual

Shirt YICHUN Digital Leisure 12 Girls Shirt Faith Wear Tunic Tops Women Trendy T Casual Thin Printed Tees Fashion wASwrZq

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