如何使用if语句在"flutter / dart“中发送https post请求

import 'package:http/http.dart' as http;
import 'dart:convert';

Future<void> sendPostRequest() async {
  var url = 'https://example.com/api'; // 替换为实际的API地址

  var body = jsonEncode({'key': 'value'}); // 替换为实际的请求体

  var response = await http.post(Uri.parse(url),
      headers: {'Content-Type': 'application/json'},
      body: body);

  if (response.statusCode == 200) {
    // 请求成功
    var responseData = jsonDecode(response.body);
    // 处理响应数据
  } else {
    // 请求失败
    print('请求失败，状态码：${response.statusCode}');
  }
}

sendPostRequest();