Angular2：向AuthGuard注入服务会中断对其他服务的注入

开始一个新项目，我带了一些我的服务 .

• TokenService使用UserService检查令牌，

• UserService发布并存储当前用户，

• AuthService使用TokenService和UserService提供http标头

• Api使用AuthService获取http标头

这些服务在我上一个项目中运行良好，似乎没有任何循环依赖 .

在我的新项目中，我需要一个AuthGuard，它也会注入UserService . 一旦我将UserService添加到AuthGuard的构造函数中，Angular就无法将UserService解析为我的其他服务中的依赖项 . 一切正常，没有注入AuthGuard .

因为这似乎不仅发生在UserService上，而且发生在例如AuthService上，我猜测我的问题不是来自服务，而是来自它们提供的方式 .

app.module.ts

import { App } from './app.component';
import { AppState, InternalStateType } from './app.service';
import { GlobalState } from './global.state';
import { NgaModule } from './theme/nga.module';
import { PagesModule } from './pages/pages.module';
import {UserService} from "./services/user.service";
import {DefaultGuard} from "./pages/default.guard";
import {AuthService} from "./services/auth.service";
import {TokenService} from "./services/token.service";
import {Api} from "./services/api.service";

// Application wide providers
const APP_PROVIDERS = [
  AppState,
  GlobalState,
  UserService,
  DefaultGuard,
  AuthService,
  TokenService,
  Api
];

@NgModule({
  bootstrap: [App],
  declarations: [
    App,
  ],
  entryComponents: [
  ],
  imports: [ // import Angular's modules
    BrowserModule,
    HttpModule,
    RouterModule,
    FormsModule,
    ReactiveFormsModule,
    NgaModule.forRoot(),
    NgbModule.forRoot(),
    PagesModule,
    routing
  ],
  providers: [ // expose our Services and Providers into Angular's dependency injection
    APP_PROVIDERS
  ]
})

export class AppModule {

  constructor(public appState: AppState) {
  }
}

pages.module.ts

import { NgModule }      from '@angular/core';
import { CommonModule }  from '@angular/common';
import { routing }       from './pages.routing';
import { NgaModule } from '../theme/nga.module';
import { AppTranslationModule } from '../app.translation.module';
import { Pages } from './pages.component';

@NgModule({
  imports: [CommonModule, AppTranslationModule, NgaModule, routing],
  declarations: [Pages],
})
export class PagesModule {
}

AuthGuard default.guard.ts 用于属于pages.module.ts的路由器

import {Injectable, Inject} from "@angular/core";
import {CanActivate, Router, ActivatedRouteSnapshot, RouterStateSnapshot} from "@angular/router";
import {UserService} from "../services/user.service";

@Injectable()
export class DefaultGuard implements CanActivate {

  constructor(
    private router: Router,
    public userService: UserService
  ) {}

  public canActivate(route: ActivatedRouteSnapshot, state: RouterStateSnapshot) {
    if (!this.userService.isAdminUser()) {
      this.router.navigate(['login']);
      return false;
    }
    return true;
  }
}

我的服务依赖：

user.service.ts

constructor(
    private http: Http,
  ) {
  }

api.service.ts

constructor(
    private http: Http,
    private auth: AuthService,
  ) {
  }

auth.service.ts

constructor(
    public userService: UserService,
    private tokenService: TokenService,
    private http: Http,
  ) {}

token.service.ts

constructor(
    public userService: UserService
  ) {
  }

所以回顾一下：在将UserService注入DefaultGuard之前，一切正常 . 将UserService注入DefaultGuard会导致TokenService中的依赖项解决错误 . 将AuthService注入DefaultGuard会导致ApiService中的依赖性解决错误等 .

关于什么错误的想法在这里？

Update 因此，似乎导入和/或注入服务的顺序在此问题中起作用 . 虽然我不确定究竟是怎么回事 .