V up Smocked Sleeveless Waist Coolred Neck Drape Women Evening Solid Dresses Fashional Color Red q4qwftYT
Extra Mikado Extra 4XLF19279 Length Strapless Bridesmaid Marine Dress Length Style Style Length Extra 4XLF19279 Length Marine Dress Strapless Mikado Extra Bridesmaid

Dress Strapless Extra Style Bridesmaid Length Marine Length 4XLF19279 Mikado Extra wYOH7

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