http - Angular 2 : Can't inject service in providers with useFactory

Question

我实现了 http 拦截器服务，它可以工作，但我的问题是我不知道如何在提供声明中注入(inject)我自己的服务。

我在控制台中收到运行时错误:No provider for MyService。

HttpService拦截器类:

// all the imports...

@Injectable()
export class HttpService extends Http {
  constructor(backend: ConnectionBackend,
              defaultOptions: RequestOptions,
              private router: Router,
              private injector: ReflectiveInjector,
              private myService: MyService){
    super(backend, defaultOptions);
  }

  // methods...

在我的 app.module.ts 中，我有一组提供者:

[ 
 {  
    provide: 'MyService', 
    useClass: MyService
 },
 {
    provide: 'Http',
    useFactory: (xhrBackend: XHRBackend,
                 requestOptions: RequestOptions,
                 router: Router,
                 injector: ReflectiveInjector,
                 myService: MyService) =>
      new HttpService(xhrBackend, requestOptions, router, injector, myService),
    deps: [XHRBackend, RequestOptions, Router, Injector, MyService]
}]

我检查了几个 SO 问题/答案，但找不到类似的例子..

谢谢!

Answer 1

deps 仅说明工厂需要哪些依赖项(以便它们可以正确注入(inject))。但它实际上并不提供依赖性。您仍然需要将它添加到 providers 数组

providers: [
  MyService,
  {
    provide: 'Http',
    ...
  }
]