可以通过使用subscribe()方法来触发HTTP请求并获取服务器响应。具体如下：

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

@Injectable({
  providedIn: 'root'
})
export class MyService {
  constructor(private http: HttpClient) {}

  getData(): Observable {
    return this.http.get('https://my-api.com/data');
  }
}

在组件中调用该服务方法可以使用该方法返回的Observable对象，并通过subscribe()方法来处理响应数据:

import { Component, OnInit } from '@angular/core';
import { MyService } from './my.service';

@Component({
  selector: 'app-my-component',
  templateUrl: './my-component.html'
})
export class MyComponent implements OnInit {
  data: any;

  constructor(private myService: MyService) {}

  ngOnInit() {
    this.myService.getData().subscribe(res => {
      // 处理响应数据
      this.data = res;
    });
  }
}