Angular 9服务使用Observables/BehaviorSubject通过父ID返回结果

import { Injectable } from '@angular/core';
import { Observable, BehaviorSubject } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class ServiceNameService {
  private resultSubject: BehaviorSubject<any> = new BehaviorSubject<any>(null);
  public result$: Observable<any> = this.resultSubject.asObservable();

  constructor() { }

  public getResultById(id: number): void {
    // 根据父ID获取结果的逻辑，可以是从服务器获取数据的异步操作
    // 将结果保存到resultSubject中
    this.resultSubject.next(result);
  }
}

import { Component, OnInit } from '@angular/core';
import { ServiceNameService } from 'path-to-service/service-name.service';

@Component({
  selector: 'app-your-component',
  templateUrl: './your-component.component.html',
  styleUrls: ['./your-component.component.css']
})
export class YourComponentComponent implements OnInit {
  public result: any;

  constructor(private serviceNameService: ServiceNameService) { }

  ngOnInit(): void {
    this.serviceNameService.result$.subscribe(result => {
      this.result = result;
    });
  }

  public getResultById(id: number): void {
    this.serviceNameService.getResultById(id);
  }
}

<button (click)="getResultById(123)">Get Result</button>
<div>{{ result }}</div>