flutter_windmill/lib/models/user_model.dart

class UserModel {
  int id = 0;
  String userName = "";
  // String
  int sex = 0;
  int age = 18;

  UserModel({
    required this.id,
    required this.userName,
    required this.sex,
    required this.age,
  });

  static UserModel fromJson(Map<String, dynamic> json) {
    return UserModel(
      id: json['id'] ?? 0,
      userName: json['userName'] ?? "",
      sex: json['sex'] ?? 0,
      age: json['age'] ?? 18,
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'userName': userName,
      'sex': sex,
      'age': age,
    };
  }
}