Angular 9:forkJoin 订阅不工作

Angular 9: forkJoin subscribe not working

我正在尝试使用 observables (rxjs 6.5.1) 在 Angular 9 的顶级组件上加载页面数据。当我单独订阅这些服务中的每一项时,我可以看到返回的数据很好:

ngOnInit(): void {
  const technicianSubscription = this.techniciansClientService.getByTechnicianId(this.technicianId).subscribe(technician => console.log(technician));
  const technicianReviewsSubscription = this.technicianReviewsClientService.getByTechnicianId(this.technicianId).subscribe(technicianReviews => console.log(technicianReviews));
}

当我尝试使用 forkJoin 时,从未返回订阅方法的数据:

ngOnInit(): void {
  this.pageDataSubscription = forkJoin({
    technician: this.techniciansClientService.getByTechnicianId(this.technicianId),
    technicianReviews: this.technicianReviewsClientService.getByTechnicianId(this.technicianId),
  }).subscribe(
    // data is never logged here
    data => console.log(data)
  );
}

我试过传递 forkJoin 一组服务调用,我也试过使用 zip,但无济于事。这里发生了什么?

我建议使用 rxjs 中的 combineLatest。它更易于使用

import {combineLatest} from `rxjs`;

componentIsActive = true;
ngOnInit(): void {
  combineLatest([
    this.techniciansClientService.getByTechnicianId(this.technicianId),
    this.technicianReviewsClientService.getByTechnicianId(this.technicianId),
  ]).pipe(
    map(([technician, technicianReviews]) => ({technician, technicianReviews})),
    takeWhile(() => this.componentIsActive)
  ).subscribe(data => console.log(data));
}