如何在Angular 8中使用Observable和pipe()返回？

import { Observable } from 'rxjs';
import { map, filter, catchError } from 'rxjs/operators';

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import { Observable } from 'rxjs';
import { map } from 'rxjs/operators';

@Injectable()
export class UserService {
  constructor(private http: HttpClient) {}

  getUsers(): Observable<any[]> {
    return this.http.get<any[]>('api/users').pipe(
      map(response => response.data)
    );
  }
}

import { Component, OnInit } from '@angular/core';
import { UserService } from './user.service';

@Component({
  selector: 'app-user-list',
  template: `
    <ul>
      <li *ngFor="let user of users">{{ user.name }}</li>
    </ul>
  `,
  providers: [UserService]
})
export class UserListComponent implements OnInit {
  users: any[];

  constructor(private userService: UserService) {}

  ngOnInit() {
    this.userService.getUsers().subscribe(
      users => this.users = users
    );
  }
}