Question

这是我的长度为1的JSON数组的代码，该数组返回长度为0的结果：

class profilInfo {
  final List<information> result;
  profilInfo._({ this.result});
  factory profilInfo.fromJson(Map jsonMap) {
    return new profilInfo._(
        result : (jsonMap['result'] as List).map((i) =>
            information.fromJson(i)).toList()
    );
  }
}

class information{
  final String firstname;
  final String country;
  final String city;
  final String about;
  final String profilephoto;
  information._({
    this.firstname,this.country,this.about,this.city,this.profilephoto});
    factory information.fromJson(Map jsonMap) {
    return new information._(
      firstname : jsonMap['first_name'],
      country : jsonMap['country'],
      city : (jsonMap['city']),
      about : (jsonMap['about']),
      profilephoto : (jsonMap['profile_photo']),
    );
  }
}

我有一个JSON文件：

{
  "status": 200,
  "result": [
    {
      "username": "mohammad",
      "password": "202cb962ac59075b964b07152d234b70",
      "create_date": "2019-08-13T08:53:24.997Z",
      "modify_date": "2019-08-13T08:53:24.997Z",
      "last_pay_date": null,
      "first_name": "mohammad reza shabani",
      "last_name": " ",
      "country": "usa",
      "city": "alai",
      "phone": "09120564589",
      "users_id": [],
      "profile_photo": "",
      "about": "",
      "_id": "5d527a84abe6713aacc62453",
      "__v": 0
    }
  ]
}

我收到此错误：

[ERROR：flutter / lib / ui / ui_dart_state.cc（148）]未处理的异常：RangeError（索引）：无效值：有效值范围为空：0

Answer 1

尝试以下代码：-

class profilInfo {
  final List<information> result;

  profilInfo._({this.result});

  factory profilInfo.fromJson(Map jsonMap) {
    List<information> informationList = new List();

    var infoList = jsonMap['result'] as List;
    informationList =
        infoList.map((i) => information.fromJson(i)).toList();

    return new profilInfo._(result: informationList);
  }
}

class information {
  final String firstname;
  final String country;
  final String city;
  final String about;
  final String profilephoto;

  information._(
      {this.firstname, this.country, this.about, this.city, this.profilephoto});

  factory information.fromJson(Map<String, dynamic> jsonMap) {
    return new information._(
      firstname: jsonMap['first_name'],
      country: jsonMap['country'],
      city: jsonMap['city'],
      about: jsonMap['about'],
      profilephoto: jsonMap['profile_photo'],
    );
  }
}

Answer 2

我建议您使用这个很棒的网站quik_types 要创建将json对象转换为数据模型所需的类和函数，只需给他一个需要转换的json对象，其余的就交给他。它更快，输入更安全，因此可以节省许多不必要的工作和时间

如何在Flutter中解析长度为1的JSON数组？

2 个答案: