如何在取消订阅的情况下通过Angular HttpClient发送POST请求？

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

constructor(private http: HttpClient) { }

sendPostRequest(url: string, data: any): Observable<any> {
  return this.http.post(url, data);
}

const request = this.sendPostRequest('https://example.com/api', postData).subscribe(
  response => {
    // 处理成功响应的逻辑
  },
  error => {
    // 处理错误响应的逻辑
  }
);

request.unsubscribe();