通过例子比较了
HttpClient,http和dio,github star和功能丰富性，选择在项目中使用dio请求网络; json_serializable+json_annotation可以作为json序列化方式，不喜欢这种方式;我选择的在https://javiercbk.github.io/json_to_dart/把基类json生成dart class实体类，
其他类使用插件FlutterJsonBeanFactory生成dart class实体类，插件安装后记得重启IDE
pubspec.yaml 添加 dio依赖
dio: ^3.0.9网络工具类
import 'dart:convert'; import 'dart:io'; import 'package:dio/dio.dart'; class HttpManager { static HttpManager _instance; static HttpManager getInstance() { if (_instance == null) { _instance = new HttpManager(); } return _instance; } HttpManager() { dio = createInstance(); } /// global dio object static Dio dio; /// default options static const String _BASE_URL = "https://www.wanandroid.com/"; static const int _CONNECT_TIMEOUT = 15000; static const int _RECEIVE_TIMEOUT = 15000; /// http request methods static const String GET = 'get'; static const String POST = 'post'; static const String PUT = 'put'; static const String PATCH = 'patch'; static const String DELETE = 'delete'; get<T>( String url, FormData param, Function onSuccess, Function onError) async { requestHttp<T>( url, param: param, method: GET, onSuccess: onSuccess, onError: onError, ); } post<T>( String url, FormData param, Function onSuccess, Function onError) async { requestHttp<T>( url, param: param, method: POST, onSuccess: onSuccess, onError: onError, ); } /// T is Map<String,dynamic> or List<dynamic> static requestHttp<T>( String url, { param, method, Function(T map) onSuccess, Function(String error) onError, }) async { dio = createInstance(); try { Response response = await dio.request( url, data: param, options: new Options(method: method), ); if (response.statusCode == HttpStatus.ok) { onSuccess(json.decode(response.data)); } else { onError("【statusCode】${response.statusCode}"); } } on DioError catch (e) { /// 打印请求失败相关信息 print("【请求出错】${e.toString()}"); onError(e.toString()); } } /// 创建 dio 实例对象 static Dio createInstance() { if (dio == null) { /// 全局属性：请求前缀、连接超时时间、响应超时时间 var options = new BaseOptions( baseUrl: _BASE_URL, connectTimeout: _CONNECT_TIMEOUT, receiveTimeout: _RECEIVE_TIMEOUT, responseType: ResponseType.plain, // contentType: Headers.jsonContentType, ); dio = new Dio(options); dio.interceptors.add(new LogInterceptors()); } return dio; } // /// request method // static Future<Map> request<T>( // String url, { // param, // method, // Function onSuccess, // Function onError, // }) async { param = param ?? {}; // // /// restful 请求处理 // /// /gysw/search/hist/:user_id user_id=27 // /// 最终生成 url 为 /gysw/search/hist/27 // param.forEach((key, value) { // if (url.indexOf(key) != -1) { // url = url.replaceAll(':$key', value.toString()); // } // }); // // dio = createInstance(); // var result; // try { // Response response = await dio.request( // url, // data: param, // options: new Options(method: method), // ); // result = json.decode(response.data); // if (response.statusCode == HttpStatus.ok) { // onSuccess(result); // } else { // onError("【statusCode】${response.statusCode}"); // } // } on DioError catch (e) { // /// 打印请求失败相关信息 // print("【请求出错】${e.toString()}"); // onError(e.toString()); // } // return result; // } /// 清空 dio 对象 static clear() { dio = null; } } ///日志拦截器 class LogInterceptors extends InterceptorsWrapper { @override Future onRequest(RequestOptions options) { print("【请求baseUrl】${options.baseUrl}"); print("【请求path】${options.path}"); print("【请求headers】${options.headers.toString()}"); //todo 参数拦截 print("【请求参数】${options.data.toString()}"); return super.onRequest(options); } @override Future onResponse(Response response) { print("【返回statusCode】${response.statusCode}"); print("【返回headers】${response.headers.toString()}"); print("【返回extra】${response.extra.toString()}"); print("【返回data】${response.data.toString()}"); return super.onResponse(response); } @override Future onError(DioError err) { print(err.toString()); print(err.response?.toString()); return super.onError(err); } }相应基类定义
///convert和FlutterJsonBeanFactory结合解析 class BaseEntity<T> { T data; int errorCode; String errorMsg; BaseEntity({this.data, this.errorCode, this.errorMsg}); BaseEntity.fromJson(Map<String, dynamic> json) { if (json['data'] != null&&json['data']!='null') { data = JsonConvert.fromJsonAsT<T>(json['data']); } errorCode = json['errorCode']; errorMsg = json['errorMsg']; } Map<String, dynamic> toJson() { final Map<String, dynamic> data = new Map<String, dynamic>(); if (this.data != null) { data['data'] = this.data; } data['errorCode'] = this.errorCode; data['errorMsg'] = this.errorMsg; return data; } } JsonConvert.fromJsonAsT<T>(json['data']); 是FlutterJsonBeanFactory生成的，判断了Object或List类型分别解析使用
HttpManager.getInstance().get("banner/json", null, (data) { BaseEntity<List<BannerEntity>> baseEntity = BaseEntity.fromJson(data); baseEntity.data.forEach((element) { print(element.imagePath); }); }, (error) { ToastUtil.showToastCenter(error); });post请求
var map = Map<String, String>(); map["username"] = "江渚清沨"; map["password"] = "xxxxx"; FormData formData = FormData.fromMap(map); HttpManager.getInstance().post("user/login", formData, (data) { BaseEntity<UserEntity> baseModel = BaseEntity.fromJson(data); print("解析${baseModel.errorMsg}"); }, (error) { ToastUtil.showToastCenter(error); });代码地址 https://gitee.com/jiangzhuqingfeng/flutter_demo.git
