defineInjectable

function

Construct an InjectableDef which defines how a token will be constructed by the DI system, and in which injectors (if any) it will be available.

      
      defineInjectable<T>(opts: { providedIn?: Type<any> | "root" | "any"; factory: () => T; }): never

opts object

never

说明

This should be assigned to a static ngInjectableDef field on a type, which will then be an InjectableType.

Options:

providedIn determines which injectors will include the injectable, by either associating it with an @NgModule or other InjectorType, or by specifying that this injectable should be provided in the 'root' injector, which will be the application-level injector in most apps.
factory gives the zero argument function which will create an instance of the injectable. The factory can call inject to access the Injector and request injection of dependencies.