格式化 Json 中的 C# MVC 返回列表

Question

有一个以 Json 形式返回的列表，但希望将其格式化如下。无法弄清楚为什么我似乎无法正确格式化它。

[{
    "AppFormName": "TFB Test Application",
    "Questions": [{
        "QuestionName": "How old are you?",
        "QuestionType": 1
    },
    {
        "QuestionName": "Where are you from?",
        "QuestionType": 1
    }]
},
{
    "AppFormName": "HLL",
    "Questions": [{
        "QuestionName": "How old are you?",
        "QuestionType": 1
    },
    {
        "QuestionName": "Where are you from?",
        "QuestionType": 1
    },
    {
        "QuestionName": "What Game are you applying for?",
        "QuestionType": 2
    },
    {
        "QuestionName": "Do you agree to the clan rules",
        "QuestionType": 3
    }]
}]

这是我的代码当前生成的：

[
    {
        "AppFormName": "TFB Test Application",
        "QuestionName": "How old are you?",
        "QuestionType": 1
    },
    {
        "AppFormName": "TFB Test Application",
        "QuestionName": "Where are you from?",
        "QuestionType": 1
    },
    {
        "AppFormName": "HLL",
        "QuestionName": "How old are you?",
        "QuestionType": 1
    },
    {
        "AppFormName": "HLL",
        "QuestionName": "Where are you from?",
        "QuestionType": 1
    },
    {
        "AppFormName": "HLL",
        "QuestionName": "What Game are you applying for?",
        "QuestionType": 2
    },
    {
        "AppFormName": "HLL",
        "QuestionName": "Do you agree to the clan rules",
        "QuestionType": 3
    }
]

这是我试图序列化结果的控制器；

public ActionResult AccessToken(string authorizationCode)
{
    UserFunctions.AccessToken(authorizationCode);
    var results = UserFunctions.userApplications;

    return Json(results , JsonRequestBehavior.AllowGet);
}

型号：

public class UserApplications
{
    public string AppFormName { get; set; }
    public string QuestionName { get; set; }
    public int QuestionType { get; set; }
}

获取数据的函数；

   public static List<Models.UserApplications> GetUserApplications(string ClientId)
    {
        userApplications.Clear();

        var getUserApplications = getUserApplicationsSQL;

        using (var conn = new MySqlConnection(dataConn))
        {
            using (var cmd = new MySqlCommand(getUserApplications, conn))
            {
                cmd.CommandType = CommandType.Text;
                cmd.Parameters.AddWithValue("@DiscordClientID", ClientId);
                cmd.Connection.Open();
                using (var dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
                {
                    while (dr.Read())
                    {
                        var u = new Models.UserApplications
                        {
                            AppFormName = dr["AppFormName"].ToString(),
                            QuestionName = dr["QuestionName"].ToString(),
                            QuestionType = dr.GetInt32(dr.GetOrdinal("TypeID")),
                        };
                        userApplications.Add(u);
                    }
                }
            }
        }

        return userApplications;
    }

Answer 1

您需要代码将现有数据结构转换为可生成所需 JSON 结构的数据结构。这可以使用 Linq 相对容易地完成。然后您需要在您的操作方法中返回该列表：

public ActionResult AccessToken(string authorizationCode)
{
    UserFunctions.AccessToken(authorizationCode);
    var results = UserFunctions.userApplications;

    var appFormList = results.GroupBy(s => s.AppFormName).Select(g => new
    {
      AppFormName = g.Key, Questions = g.Select(a => new
      {
        a.QuestionName, 
        a.QuestionType
      })
    });

    return Json(appFormList, JsonRequestBehavior.AllowGet);
}

现场演示：https://dotnetfiddle.net/sRIy72

（感谢 this post 使用 Linq 的想法。）

Answer 2

这可以简单地通过分组来实现：

public ActionResult AccessToken(string authorizationCode)
{
    UserFunctions.AccessToken(authorizationCode);
    List<UserApplications> results = UserFunctions.userApplications;
    var data = from p in results 
           group p by p.AppFormName into g
           select new { AppFormName = g.Key, Questions = g.Select(x=> new { QuestionName = x.QuestionName, QuestionType = x.QuestionType}).ToList() };

    return Json(data , JsonRequestBehavior.AllowGet);
}