Question

我试图显示用户在标头中的通知数量，并每隔5秒轮询一次。

我有通知服务：

export class NotificationService {
  readonly baseUrl = `${environment.apiUrl}/notification`;

  constructor(private http: HttpClient) { }

  public getNotificationCountForUser(userid): Observable<number> {
    return Observable.interval(5000)
    .switchMap(() => this.http.get<number>(this.baseUrl + '/getNotificationCountForUser?UserId=' + userid));
  }

我正在尝试将此加载到我的标题中的BehaviorSubject：

    export class HeaderComponent implements OnInit {

        private notificationCountSubject = new BehaviorSubject<number>(0);
        notificationCount = this.notificationCountSubject.asObservable().share();

        constructor(private, private notificationService: NotificationService,
            private router: Router) { }

        ngOnInit() {
             this.notificationCountSubject.next(this.notificationService.getNotificationsForUser(this.currentUser.id));
              // I get the user id from a separate function, have left it out in my question

                }
            })

        }

我的this.notificationCountSubject.next语法不正确，我应该传递一个号码，但我传递的是Observable而我不确定如何处理此问题。< / p>

我应该在我的服务中加载BehaviorSubject而不是我的组件吗？然后我会通过什么？

更新

我已尝试将此全部内容放入我的通知服务中：

export class NotificationService {
  readonly baseUrl = `${environment.apiUrl}/notification`;

  private notificationCountSubject = new BehaviorSubject<number>(0);
    public readonly notificationCount = this.notificationCountSubject.asObservable();

  constructor(private http: HttpClient) { }

  public getNotificationCountForUser(userid): Observable<number> {

    return this.notificationCountSubject.next(
      Observable.interval(5000)
      .switchMap(() => this.http.get<number>(this.baseUrl + '/getNotificationCountForUser?UserId=' + userid))
    );     
  }

但得到＆＃39;类型＆＃39; Observable＆＃39;不能分配给＆＃39;数字＆＃39;。＆＃39;

类型的参数

Angular 5 BehaviorSubject由Observable查询填充

0 个答案: