我在 flutter 中像下面的代码一样从键和值中解析 JSON

 Future<LoginBean> login() async {
    var body = json.encode({"MOB": "1112223330", "KEY": "123456"});

    return http.post(
        Uri.encodeFull(
            "https://MY_Server/Users/login"),
        body: body.toString(),
        headers: {'Content-type': 'application/json'}).then((response) {
      print("Response Status : $response");

      if (response.statusCode == 200) {
         Map userMap = jsonDecode(json);
         var user = new LoginBean.fromJson(userMap);

         debugPrint("here is the response==>>>> $user");
      }
    });
  }

有没有其他方法像我们在 Android 中那样在 Model 类中解析 JSON，请查看下面的示例。

Gson gson = new Gson();

MY_LOGIN_BEAN loginBean = gson.fromJson(response, MY_LOGIN_BEAN.class);

我已经引用了这个链接但没有得到解决方案，请检查以下内容:-
1). Link
2). Link
3). Link

这是我的 JSON 响应

{"status":1,"message":"Login Successfully","data":{"userid":"101","Authorization":"eyJ1c2VyaWQiOiIxMDEiLCJ0b2tlbiI6IjVjYWRkYzUzMWY4YzAifQ==","roles":"2","firstname":"Ravindra","lastname":"kushwaha","fullname":"Ravindra kushwaha","wallet_amount":"845.00","mobile":"1112223330","email":"ravindra.kushwaha@consagous.com","chat_id":"","qrcode_image":"https:\/\/dapplepay.consagous.co.in\/uploads\/coupon_qr\/11C1f7ApJM8r.png","redirect_to_verify":"0","notification_status":"0","country_code":"91","Is_Allowed_Transaction":"1","profile_image":"https:\/\/dapplepay.consagous.co.in\/uploads\/user\/1553600479DapplePay1553600454461.png","fingerprint_status":"0"}}

我已经尝试了下面的代码行，请看一下，但我没有得到任何成功。

  class LoginBean {
  int status;
  String message;
  Data data;

  LoginBean({
    this.status,
    this.message,
    this.data,
  });


  static Map<String, dynamic> toMap(LoginBean loginBean){
    var map = Map<String, dynamic>();
    map['status'] = loginBean.status;
    map['message'] = loginBean.message;
    map['data'] = Data.toMap(loginBean);
    return map;
  }

  LoginBean.map(dynamic obj) {
    this.status = obj["status"];
    this.message = obj["message"];
    if (obj['data'] != null) {
      this.data = new Data.map(obj['data']);
    }
  }

  factory LoginBean.fromJson(dynamic json) {
    print('here we gooo');
    return LoginBean(
        status: json['status'],
        message: json['message'],
        data: new Data.fromJson(json['data'])
    );
  }

}

class Data {
  String userid;
  String authorization;
  String roles;
  String firstname;
  String lastname;
  String fullname;
  String walletAmount;
  String mobile;
  String email;
  String chatId;
  String qrcodeImage;
  String redirectToVerify;
  String notificationStatus;
  String countryCode;
  String isAllowedTransaction;
  String profileImage;
  String fingerprintStatus;


  Data.map(dynamic json) {
    this.userid = json['userid'];
    this.authorization = json['authorization'];
    this.roles = json['roles'];
    this.firstname = json['firstname'];
    this.lastname = json['lastname'];
    this.fullname = json['fullname'];
    this.walletAmount = json['walletAmount'];
    this.mobile = json['mobile'];
    this.email = json['email'];
    this.chatId = json['chatId'];
    this.qrcodeImage = json['qrcodeImage'];
    this.redirectToVerify = json['redirectToVerify'];
    this.notificationStatus = json['notificationStatus'];
    this.countryCode= json['countryCode'];
    this.isAllowedTransaction = json['isAllowedTransaction'];
    this.profileImage = json['profileImage'];
    this.fingerprintStatus = json['fingerprintStatus'];
  }


  static Map<String, dynamic> toMap(LoginBean loginBean){
    var map = Map<String, dynamic>();
    map['userid'] = loginBean.data.userid;
    map['authorization'] = loginBean.data.authorization;
    map['roles'] = loginBean.data.roles;
    map['firstname'] = loginBean.data.firstname;
    map['lastname'] = loginBean.data.lastname;
    map['fullname'] = loginBean.data.fullname;
    map['walletAmount'] = loginBean.data.walletAmount;
    map['mobile'] = loginBean.data.mobile;
    map['email'] = loginBean.data.email;
    map['chatId'] = loginBean.data.chatId;
    map['qrcodeImage'] = loginBean.data.qrcodeImage;
    map['redirectToVerify'] = loginBean.data.redirectToVerify;
    map['notificationStatus'] = loginBean.data.notificationStatus;
    map['countryCode'] = loginBean.data.countryCode;
    map['isAllowedTransaction'] = loginBean.data.isAllowedTransaction;
    map['profileImage'] = loginBean.data.profileImage;
    map['fingerprintStatus'] = loginBean.data.fingerprintStatus;
    return map;
  }

  factory Data.fromJson(dynamic json) {
    return Data(
      userid: json['userid'],
      authorization: json['authorization'],
      roles: json['roles'],
      firstname: json['firstname'],
      lastname: json['lastname'],
      fullname: json['fullname'],
      walletAmount: json['walletAmount'],
      mobile: json['mobile'],
      email: json['email'],
      chatId: json['chatId'],
      qrcodeImage: json['qrcodeImage'],
      redirectToVerify: json['redirectToVerify'],
      notificationStatus: json['notificationStatus'],
      countryCode: json['countryCode'],
      isAllowedTransaction: json['isAllowedTransaction'],
      profileImage: json['profileImage'],
      fingerprintStatus: json['fingerprintStatus'],

    );
  }

  Data({
    this.userid,
    this.authorization,
    this.roles,
    this.firstname,
    this.lastname,
    this.fullname,
    this.walletAmount,
    this.mobile,
    this.email,
    this.chatId,
    this.qrcodeImage,
    this.redirectToVerify,
    this.notificationStatus,
    this.countryCode,
    this.isAllowedTransaction,
    this.profileImage,
    this.fingerprintStatus,
  });
}

当我使用模型类解析 JSON 时，我从上面的代码中得到以下异常

2019-04-10 18:59:28.553 11121-11153/democom.first_flutter_app E/flutter: [ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: type '_InternalLinkedHashMap<String, dynamic>' is not a subtype of type 'String'
    #0      _LoginScreen.login.<anonymous closure> (package:first_flutter_app/onBording/login_screen.dart:139:34)
    #1      _rootRunUnary (dart:async/zone.dart:1132:38)
    #2      _CustomZone.runUnary (dart:async/zone.dart:1029:19)
    #3      _FutureListener.handleValue (dart:async/future_impl.dart:126:18)
    #4      Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:639:45)
    #5      Future._propagateToListeners (dart:async/future_impl.dart:668:32)
    #6      Future._complete (dart:async/future_impl.dart:473:7)
    #7      _SyncCompleter.complete (dart:async/future_impl.dart:51:12)
    #8      _AsyncAwaitCompleter.complete (dart:async/runtime/libasync_patch.dart:28:18)
    #9      _completeOnAsyncReturn (dart:async/runtime/libasync_patch.dart:294:13)
    #10     _withClient (package:http/http.dart)
    <asynchronous suspension>
    #11     post (package:http/http.dart:70:3)
    #12     _LoginScreen.login (package:first_flutter_app/onBording/login_screen.dart:129:12)
    <asynchronous suspension>
    #13     _LoginScreen.build.<anonymous closure>.<anonymous closure> (package:first_flutter_app/onBording/login_screen.dart:102:25)
    #14     _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:513:14)
    #15     _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:568:30)
    #16     GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:120:24)
    #17     TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:242:9)
    #18     TapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:175:7)
    #19     PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:369:9)
    #20     PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:73:12)
    #21     PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:101:11)
    #22     _WidgetsFlutterBinding&BindingBase&GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:214:19)
    #23     _WidgetsFlutterBinding&BindingBase&GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:192:22)
    #24     _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:149:7)
    #25     _WidgetsFlutterBinding&BindingBase&GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:101:7)
    #26     _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:85:7)
    #27     _rootRunUnary (dart:async/zone.dart:1136:13)
    #28     _CustomZone.runUnary (dart:async/zone.dart:1029:19)
    #29     _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
    #30     _invoke1 (dart:ui/hooks.dart:223:10)
    #31     _dispatchPointerDataPacket (dart:ui/hooks.dart:144:5)

最佳答案

你正在解码 json，而你应该像这样解码响应中收到的正文 -

var userMap = jsonDecode(response?.body);

关于 flutter :- How to parse the JSON from the model class in flutter?，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/55612365/