如何在ionic2 (typescript)中将带参数的http post作为多部分/表单数据请求发送？

import { Http, Headers, Response } from '@angular/http';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/map';

sendFormData(data: any, file: File): Observable<any> {
  let url = 'YOUR_API_URL'; // 替换为实际的API URL

  // 创建FormData对象
  let formData: FormData = new FormData();
  formData.append('param1', data.param1); // 添加参数
  formData.append('param2', data.param2);
  formData.append('file', file, file.name); // 添加文件

  // 创建请求头
  let headers = new Headers();
  headers.append('Content-Type', 'multipart/form-data');

  // 发送POST请求
  return this.http.post(url, formData, { headers: headers })
    .map((res: Response) => res.json());
}

let data = {
  param1: 'value1',
  param2: 'value2'
};

let file: File = // 获取文件对象

this.sendFormData(data, file)
  .subscribe(response => {
    // 处理响应
  }, error => {
    // 处理错误
  });