angular - 将http客户端注入(inject)HTTP拦截器Angular 4

Question

如何将http客户端注入(inject)HTTP拦截器？每当我这样做时，它都会抛出:未捕获错误:提供程序解析错误: 无法实例化循环依赖! InjectionToken_HTTP_INTERCEPTORS ("[ERROR ->]"): 在 ./AppModule@-1:-1 中的 NgModule AppModule

我的拦截器看起来像:

@Injectable()
export class CustomHttpInterceptor implements HttpInterceptor {

  constructor(private ehs: ErrorHandlerService,
              private localStorageService: LocalStorageService,
              private router: Router,
              private http: HttpClient
             ){}

Answer 1

你可以使用注入(inject)器

  constructor(inj: Injector) {
    this.auth = inj.get(AuthService)
  }

看这个例子: https://plnkr.co/edit/8CpyAUSJcCiRqdZmuvt9?p=preview

https://angular.io/api/core/Injector

关于此问题的长讨论:https://github.com/angular/angular/issues/18224