using System;

using System.Collections.Generic;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        string json = @"

            {

              ""KnownPropName"": [

                {

                  ""DynamicPropName"": [

                    {

                      ""KnownProp1"": ""value 1"",

                      ""KnownProp2"": ""value 2""

                    },

                    {

                      ""KnownProp1"": ""value 3"",

                      ""KnownProp2"": ""value 4""

                    }

                  ]

                }

              ]

            }";

        var resp = JsonConvert.DeserializeObject<TestResponse>(json);

        foreach (var dict in resp.KnownPropName)

        {

            foreach (var kvp in dict)

            {

                Console.WriteLine(kvp.Key);

                foreach (var item in kvp.Value)

                {

                    Console.WriteLine("KnownProp1: " + item.KnownProp1);

                    Console.WriteLine("KnownProp2: " + item.KnownProp2);

                }

            }

        }

    }

    private class TestResponse

    {

        public Dictionary<string, TestInner[]>[] KnownPropName { get; set; }

    }

​

    private class TestInner

    {

        public string KnownProp1 { get; set; }

        public string KnownProp2 { get; set; }

    }   

}