Flutter Dio二次封装的实现

程序员文章站 2022-03-14 10:50:35

目录： diomanager：dio辅助类nwmethod：请求方法，get、post等 nwapi：大家都知道 entityfactory：json转换辅助工厂...

目录：

diomanager：dio辅助类nwmethod：请求方法，get、post等
nwapi：大家都知道
entityfactory：json转换辅助工厂，把json转为t
baseentity<t>：数据基类，返回的参数为 {“code”: 0, “message”: “”, “data”: {}}
baselistentity<t>：数据基类2，返回的参数为 {“code”: 0, “message”: “”, “data”: []}
errorentity：请求报错基类，{“code”: 0, “message”: “”}

entityfactory：

class entityfactory {
 static t generateobj<t>(json) {
  if (json == null) {
   return null;
  }
//可以在这里加入任何需要并且可以转换的类型，例如下面
//  else if (t.tostring() == "loginentity") {
//   return loginentity.fromjson(json) as t;
//  }
  else {
   return json as t;
  }
 }
}

baseentity：

class baseentity<t> {
 int code;
 string message;
 t data;

 baseentity({this.code, this.message, this.data});

 factory baseentity.fromjson(json) {
  return baseentity(
   code: json["code"],
   message: json["msg"],
   // data值需要经过工厂转换为我们传进来的类型
   data: entityfactory.generateobj<t>(json["data"]),
  );
 }
}

baselistentity：

class baselistentity<t> {
 int code;
 string message;
 list<t> data;

 baselistentity({this.code, this.message, this.data});

 factory baselistentity.fromjson(json) {
  list<t> mdata = list();
  if (json['data'] != null) {
   //遍历data并转换为我们传进来的类型
   (json['data'] as list).foreach((v) {
    mdata.add(entityfactory.generateobj<t>(v));
   });
  }

  return baselistentity(
   code: json["code"],
   message: json["msg"],
   data: mdata,
  );
 } }

errorentity：

class errorentity {
 int code;
 string message;
 errorentity({this.code, this.message});
}

nwapi：

class nwapi {
 static final baseapi = "https://easy-mock.bookset.io/mock/5dfae67d4946c20a50841fa7/example/";
 static final loginpath = "user/login";//接口返回：{"code": int, "message": "string", "data": {"account": "string", "password": "string"}}
 static final querylistpath = "/query/list";//接口返回：{"code": ing, "message": "string", "data": [int, int, string, int, string, int]}
 static final querylistjsonpath = "/query/listjson";//接口返回：{"code": int, "message": "string", "data": [{"account": "string", "password": "string"}， {"account": "string", "password": "string"}]}
}

nwmethod：

enum nwmethod {
 get,
 post,
 delete,
 put
}
//使用：nwmethodvalues[nwmethod.post]
const nwmethodvalues = {
 nwmethod.get: "get",
 nwmethod.post: "post",
 nwmethod.delete: "delete",
 nwmethod.put: "put"
};

下面就可以进行正式的封装了：

第一步是创建dio的单例辅助类，并初始化dio和对dio进行一些全局的参数设置：

import 'package:dio/dio.dart';
import 'package:flutter_app/network/nwapi.dart';
import 'package:flutter_app/utils/printutil.dart';
class diomanager {
 static final diomanager _shared = diomanager._internal();
 factory diomanager() => _shared;
 dio dio;
 diomanager._internal() {
  if (dio == null) {
   baseoptions options = baseoptions(
    baseurl: nwapi.baseapi,
    contenttype: headers.jsoncontenttype,
    responsetype: responsetype.json,
    receivedatawhenstatuserror: false,
    connecttimeout: 30000,
    receivetimeout: 3000,
   );
   dio = dio(options);
  }
 }
}

第二步对请求进行封装，在我的想法中 {“code”: 0, “message”: “”, “data”: {}} 和 {“code”: 0, “message”: “”, “data”: []} 这两种数据是要分开两个请求方法的：

 // 请求，返回参数为 t
 // method：请求方法，nwmethod.post等
 // path：请求地址
 // params：请求参数
 // success：请求成功回调
 // error：请求失败回调
 future request<t>(nwmethod method, string path, {map params, function(t) success, function(errorentity) error}) async {
  try {
   response response = await dio.request(path, queryparameters: params, options: options(method: nwmethodvalues[method]));
   if (response != null) {
    baseentity entity = baseentity<t>.fromjson(response.data);
    if (entity.code == 0) {
     success(entity.data);
    } else {
     error(errorentity(code: entity.code, message: entity.message));
    }
   } else {
    error(errorentity(code: -1, message: "未知错误"));
   }
  } on dioerror catch(e) {
   error(createerrorentity(e));
  }
 }

 // 请求，返回参数为 list
 // method：请求方法，nwmethod.post等
 // path：请求地址
 // params：请求参数
 // success：请求成功回调
 // error：请求失败回调
 future requestlist<t>(nwmethod method, string path, {map params, function(list) success, function(errorentity) error}) async {
  try {
   response response = await dio.request(path, queryparameters: params, options: options(method: nwmethodvalues[method]));
   if (response != null) {
    baselistentity entity = baselistentity<t>.fromjson(response.data);
    if (entity.code == 0) {
     success(entity.data);
    } else {
     error(errorentity(code: entity.code, message: entity.message));
    }
   } else {
     error(errorentity(code: -1, message: "未知错误"));
   }
  } on dioerror catch(e) {
   error(createerrorentity(e));
  }
 }

提取请求错误处理方法createerrorentity：

 // 错误信息
 errorentity createerrorentity(dioerror error) {
  switch (error.type) {
   case dioerrortype.cancel:{
    return errorentity(code: -1, message: "请求取消");
   }
   break;
   case dioerrortype.connect_timeout:{
    return errorentity(code: -1, message: "连接超时");
   }
   break;
   case dioerrortype.send_timeout:{
    return errorentity(code: -1, message: "请求超时");
   }
   break;
   case dioerrortype.receive_timeout:{
    return errorentity(code: -1, message: "响应超时");
   }
   break;
   case dioerrortype.response:{
    try {
     int errcode = error.response.statuscode;
     string errmsg = error.response.statusmessage;
     return errorentity(code: errcode, message: errmsg);
//     switch (errcode) {
//      case 400: {
//       return errorentity(code: errcode, message: "请求语法错误");
//      }
//      break;
//      case 403: {
//       return errorentity(code: errcode, message: "服务器拒绝执行");
//      }
//      break;
//      case 404: {
//       return errorentity(code: errcode, message: "无法连接服务器");
//      }
//      break;
//      case 405: {
//       return errorentity(code: errcode, message: "请求方法被禁止");
//      }
//      break;
//      case 500: {
//       return errorentity(code: errcode, message: "服务器内部错误");
//      }
//      break;
//      case 502: {
//       return errorentity(code: errcode, message: "无效的请求");
//      }
//      break;
//      case 503: {
//       return errorentity(code: errcode, message: "服务器挂了");
//      }
//      break;
//      case 505: {
//       return errorentity(code: errcode, message: "不支持http协议请求");
//      }
//      break;
//      default: {
//       return errorentity(code: errcode, message: "未知错误");
//      }
//     }
    } on exception catch(_) {
     return errorentity(code: -1, message: "未知错误");
    }
   }
   break;
   default: {
    return errorentity(code: -1, message: error.message);
   }
  }
 }

完整的 diomanager 类代码：

import 'package:dio/dio.dart';
import 'package:flutter_app/network/entity/baseentity.dart';
import 'package:flutter_app/network/entity/baselistentity.dart';
import 'package:flutter_app/network/entity/entityfactory.dart';
import 'package:flutter_app/network/entity/errorentity.dart';
import 'package:flutter_app/network/nwapi.dart';
import 'package:flutter_app/network/nwmethod.dart';
class diomanager {
 static final diomanager _shared = diomanager._internal();
 factory diomanager() => _shared;
 dio dio;
 diomanager._internal() {
  if (dio == null) {
   baseoptions options = baseoptions(
    baseurl: nwapi.baseapi,
    contenttype: headers.jsoncontenttype,
    responsetype: responsetype.json,
    receivedatawhenstatuserror: false,
    connecttimeout: 30000,
    receivetimeout: 3000,
   );
   dio = dio(options);
  }
 }

 // 请求，返回参数为 t
 // method：请求方法，nwmethod.post等
 // path：请求地址
 // params：请求参数
 // success：请求成功回调
 // error：请求失败回调
 future request<t>(nwmethod method, string path, {map params, function(t) success, function(errorentity) error}) async {
  try {
   response response = await dio.request(path, queryparameters: params, options: options(method: nwmethodvalues[method]));
   if (response != null) {
    baseentity entity = baseentity<t>.fromjson(response.data);
    if (entity.code == 0) {
     success(entity.data);
    } else {
     error(errorentity(code: entity.code, message: entity.message));
    }
   } else {
    error(errorentity(code: -1, message: "未知错误"));
   }
  } on dioerror catch(e) {
   error(createerrorentity(e));
  }
 }

 // 请求，返回参数为 list
 // method：请求方法，nwmethod.post等
 // path：请求地址
 // params：请求参数
 // success：请求成功回调
 // error：请求失败回调
 future requestlist<t>(nwmethod method, string path, {map params, function(list<t>) success, function(errorentity) error}) async {
  try {
   response response = await dio.request(path, queryparameters: params, options: options(method: nwmethodvalues[method]));
   if (response != null) {
    baselistentity entity = baselistentity<t>.fromjson(response.data);
    if (entity.code == 0) {
     success(entity.data);
    } else {
     error(errorentity(code: entity.code, message: entity.message));
    }
   } else {
    error(errorentity(code: -1, message: "未知错误"));
   }
  } on dioerror catch(e) {
   error(createerrorentity(e));
  }
 }

 // 错误信息
 errorentity createerrorentity(dioerror error) {
  switch (error.type) {
   case dioerrortype.cancel:{
    return errorentity(code: -1, message: "请求取消");
   }
   break;
   case dioerrortype.connect_timeout:{
    return errorentity(code: -1, message: "连接超时");
   }
   break;
   case dioerrortype.send_timeout:{
    return errorentity(code: -1, message: "请求超时");
   }
   break;
   case dioerrortype.receive_timeout:{
    return errorentity(code: -1, message: "响应超时");
   }
   break;
   case dioerrortype.response:{
    try {
     int errcode = error.response.statuscode;
     string errmsg = error.response.statusmessage;
     return errorentity(code: "$errcode", message: errmsg);
//     switch (errcode) {
//      case 400: {
//       return errorentity(code: errcode, message: "请求语法错误");
//      }
//      break;
//      case 403: {
//       return errorentity(code: errcode, message: "服务器拒绝执行");
//      }
//      break;
//      case 404: {
//       return errorentity(code: errcode, message: "无法连接服务器");
//      }
//      break;
//      case 405: {
//       return errorentity(code: errcode, message: "请求方法被禁止");
//      }
//      break;
//      case 500: {
//       return errorentity(code: errcode, message: "服务器内部错误");
//      }
//      break;
//      case 502: {
//       return errorentity(code: errcode, message: "无效的请求");
//      }
//      break;
//      case 503: {
//       return errorentity(code: errcode, message: "服务器挂了");
//      }
//      break;
//      case 505: {
//       return errorentity(code: errcode, message: "不支持http协议请求");
//      }
//      break;
//      default: {
//       return errorentity(code: errcode, message: "未知错误");
//      }
//     }
    } on exception catch(_) {
     return errorentity(code: -1, message: "未知错误");
    }
   }
   break;
   default: {
    return errorentity(code: -1, message: error.message);
   }
  }
 }
}

使用：

// 返回 loginentity
diomanager().request<loginentity>(
 nwmethod.post,
 nwapi.loginpath,
 params: {"account": "421789838@qq.com", "password": "123456"},
 success: (data) {
   print("success data = $data"});
 }, error: (error) {
   print("error code = ${error.code}, massage = ${error.message}");
 }
);

// 返回 list
diomanager().requestlist<loginentity>(
 nwmethod.post,
 nwapi.querylistjsonpath,
 params: {"account": "421789838@qq.com", "password": "123456"},
 success: (data) {
   print("success data = $data"});
 }, error: (error) {
   print("error code = ${error.code}, massage = ${error.message}");
 }
);

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。

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