问读取JSON数据颤动遇到困难
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Stack Overflow用户

提问于 2021-04-14 17:08:21

回答 1查看 30关注 0票数 0

这是我的JSON数据结构：

[
  [
   {
    "nos": 0,
     "name": "A S MUSIC AND DANCE A CULTURAL ORGANIZATION",
    "unique_id": "AN/2020/0259067",
    "reg_details": [
     {
      "registered_with": "Registrar of Societies"
      },
     {
      "type_of_ngo": "Registered Societies (Non-Government)"
     },
     {
      "registration_no": "1534"
       },
       {
         "copy_of_registration_certificate": "Available"
          },
       {
         "copy_of_pan_card": "Available"
        },
       {
        "act_name": "Registration Act,1860"
        },
      {
       "city_of_registration": "Port Blair"
      },
       {
       "state_of_registration": "ANDAMAN & NICOBAR ISLANDS"
        },
         {
       "date_of_registration": "25-05-2016"
        }
      ],

在我的this函数中：

 Future<void> _NgoDetail() async {
    String jsonString = await _loadANgoAsset();
    final jsonResponse = json.decode(jsonString);
    var rest = jsonResponse[0] as List;
    List list=[];
    list= rest.map<NGO>((json) => NGO.fromJson(json)).toList();
    debugPrint(list[0].regDetails[1].type_of_ngo);
  }

当我运行这行代码时：

debugPrint(list[0].regDetails[1].type_of_ngo);

结果是好的

I/flutter ( 5579): List<dynamic>
I/chatty  ( 5579): uid=10326(com.skillzup.mn.mn) 1.ui identical 117 lines
I/flutter ( 5579): List<dynamic>
I/flutter ( 5579): Registered Societies (Non-Government)

但当我运行这段代码时：

debugPrint(list[0].regDetails[2].registration_no);

我得到了这个错误：

I/flutter ( 5579): List<dynamic>
I/chatty  ( 5579): uid=10326(com.skillzup.mn.mn) 1.ui identical 117 lines
I/flutter ( 5579): List<dynamic>
I/flutter ( 5579): null

这个也是一样的：

debugPrint(list[0].regDetails[3].copy_of_registration_certificate);

错误：

Unhandled Exception: NoSuchMethodError: Class 'RegDetails' has no instance getter 'copy_of_registration_certificate'.

我想从这个接口获得的最重要的数据是: debugPrint(list2.regDetails8.date_of_registration)；

但是我得到了这个错误：

I/flutter ( 5579): List<dynamic>
I/chatty  ( 5579): uid=10326(com.skillzup.mn.mn) 1.ui identical 117 lines
I/flutter ( 5579): List<dynamic>
I/flutter ( 5579): null

对于某些字段，数据显示正确，但对于某些字段，要么显示为空，要么显示某些错误。我遗漏了什么？

这是我的NGO和注册类：

class NGO {
  String name;
  String id;
  List<RegDetails> regDetails;
  contactDetails ContactDetails;
  Members members;
  WorkingSectors workingSectors;

  NGO(
      {this.members, this.regDetails, this.name, this.workingSectors, this.ContactDetails, this.id,});

  
  factory NGO.fromJson(Map<String, dynamic> json) {
    var list = json['reg_details'] as List;
    print(list.runtimeType);
    List<RegDetails> regDetails = list.map((i) => RegDetails.fromJson(i)).toList();


    return NGO(
      id: json["unique_id"],
      name: json['name'],
     regDetails: regDetails


    );
  }
}

class RegDetails {
  String registration_no;
  String type_of_ngo;
  String registered_with;
  String copy_of_pan_card;
  String date_of_registration;
  String city_of_registration;
  String state_of_registration;
  String FCRA;

  RegDetails(
      {this.FCRA = 'Not Available', this.city_of_registration, this.copy_of_pan_card, this.date_of_registration, this.registered_with, this.registration_no, this.state_of_registration, this.type_of_ngo});

  factory RegDetails.fromJson(Map<String, dynamic> json){
    return RegDetails(
      registration_no: json['registeration_no'],
      type_of_ngo: json['type_of_ngo'],
      registered_with: json['registered_with'],
      copy_of_pan_card: json['copy_of_pan_card'],
      date_of_registration: json['date_of_registeration'],
      city_of_registration: json['city_of_registeration'],
      state_of_registration: json['state_of_registeration'],
    );
  }
}

flutter

dart

回答 1

Stack Overflow用户

发布于 2021-04-14 18:18:30

由于这段代码中的拼写错误

  factory RegDetails.fromJson(Map<String, dynamic> json){
    return RegDetails(
      registration_no: json['registration_no'],
      type_of_ngo: json['type_of_ngo'],
      registered_with: json['registered_with'],
      copy_of_pan_card: json['copy_of_pan_card'],
      date_of_registration: json['date_of_registeration'],
      city_of_registration: json['city_of_registeration'],
      state_of_registration: json['state_of_registeration'],
    );
  }
}