Angular retrigger订阅http调用

import { HttpClient } from '@angular/common/http';

constructor(private http: HttpClient) {}

getData(): Observable<any> {
  return this.http.get('https://example.com/api/data');
}

import { Component, OnInit } from '@angular/core';

@Component({
  selector: 'app-example',
  templateUrl: './example.component.html',
  styleUrls: ['./example.component.css']
})
export class ExampleComponent implements OnInit {
  data: any;

  constructor(private service: DataService) {}

  ngOnInit() {
    this.service.getData().subscribe(response => {
      this.data = response;
      // 处理响应结果
    });
  }
}

import { Component, OnInit, OnDestroy } from '@angular/core';
import { Subscription } from 'rxjs';

@Component({
  selector: 'app-example',
  templateUrl: './example.component.html',
  styleUrls: ['./example.component.css']
})
export class ExampleComponent implements OnInit, OnDestroy {
  data: any;
  subscription: Subscription;

  constructor(private service: DataService) {}

  ngOnInit() {
    this.getData();
  }

  ngOnDestroy() {
    this.subscription.unsubscribe();
  }

  getData() {
    if (this.subscription) {
      this.subscription.unsubscribe();
    }

    this.subscription = this.service.getData().subscribe(response => {
      this.data = response;
      // 处理响应结果
    });
  }
}