Womens Side 21FASHION Dress Top Dress Split Tunic UK Neck 8 Scoop Sleeve Short Charcoal Maxi Ladies Long 14 fqSSwA
Burgundy Women Dressesonline Short Dress Prom Beading Homecoming Dress line s A line Beading Homecoming Burgundy A Women Dress Dress s Dressesonline Prom Short

line Beading Dress Dress Short Burgundy Homecoming A s Prom Dressesonline Women wqOgpg

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