Question

有一条路线负责在页面上显示用户信息。该路由具有：id参数，与用户的ID属性相对应。

const appRoutes: Routes = [
    { path: 'user/:id', component: UserDetailComponent }
];

export class User {
    id: number;
    name: string;
    age: number;
    photoUrl: string;
    info: string;
    constructor(name: string, age: number, photoUrl: string, info: string, id: number) {
        this.name = name;
        this.age = age;
        this.photoUrl = photoUrl;
        this.info = info;
        this.id = id;
    }
}

我需要检索特定的AngularFirestoreDocument，该文件包含具有路由器参数中指定的id属性/字段的用户。

如何在服务中创建getUser（id：number）方法，然后在UserDetailComponent中使用它来显示路由器参数指定的用户？

P.s。作为用户ID，我不会使用FirestoreDocument标识符，我想要自己的自定义ID值。

export class UsersService {

  usersCollection: AngularFirestoreCollection<User>;
  users: Observable<any[]>;

  constructor(private firebase: AngularFirestore) {
    this.users = firebase.collection('users').valueChanges();
   }

  getUser(id: number) {
    // How to get user with particular field(property)? 
     //For example I want to retrieve from my Cloud Firestore user with id == 1 and return it.
  }

 export class UserDetailComponent implements OnInit {

  user: User;
  userId: number;

  constructor(private usersService: UsersService, private route: ActivatedRoute) { }

  ngOnInit() {
    this.route.params
    .subscribe((params) => {
      this.userId = +params['id'];
      this.user = this.usersService.getUser(this.userId);
      });
    });
  }

如何在不订阅的情况下通过特定字段值获取AngularFirestoreDocument？

0 个答案: