using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.IO;

using System.Collections.ObjectModel;

using System.Reflection;

using System.Runtime.Serialization;

using System.Data;

using System.Xml;

​

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;

​

// https://stackoverflow.com/questions/42172420/how-to-convert-nested-json-to-csv-in-c

    public class Program

    {

        static string GetJson()

        {

            var json = @"{

 ""2017-02-11"":

  {

  ""Table1"": [

    {

      ""code"": ""code day1.1.1"",

      ""no"": ""no day1.1.1""

    }

  ],

  ""Table2"": [

    {

      ""code"": ""code day1.2.1"",

      ""no"": ""no day1.2.1""

    },

    {

      ""code"": ""code day1.2.2"",

      ""no"": ""no day1.2.2""

    }

  ]

 },

 ""2017-02-12"":

  {

  ""Table1"": [

    {

      ""code"": ""code day2.1.1"",

      ""no"": ""no day2.1.1""

    },

    {

      ""code"": ""code day2.1.2"",

      ""no"": ""no day2.1.2""

    }

  ],

  ""Table2"": [

    {

      ""code"": ""code day2.2.1"",

      ""no"": ""no day2.2.1""

    }

  ]

 }

}";

            return json;

        }

        public static void Main()

        {

            Console.WriteLine("Json.NET version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine("");

            var content = GetJson();

            // Use a sorted dictionary since the data is ordered by date.

            var dataSets = JsonConvert.DeserializeObject<SortedDictionary<DateTime, DataSet>>(content);

            Console.WriteLine("Result of parsing: ");

            Console.WriteLine(JsonConvert.SerializeObject(dataSets, Newtonsoft.Json.Formatting.Indented));

        }

    }

​