using System;

using System.Collections.Generic;

using System.Linq;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        // We only want enums used in Model1 or Model2

        var dict = GetAllEnums(typeof(Model1), typeof(Model2));

        var data = new

        {

            Code = 200,

            Message = "OK",

            Data = dict 

        };

        var json = JsonConvert.SerializeObject(data, Formatting.Indented);

        Console.WriteLine(json);

    }

    static Dictionary<string, Dictionary<string, int>> GetAllEnums(params Type[] types)

    {

        return types

            .SelectMany(t => t.GetProperties())

            .Select(p => p.PropertyType)

            .Where(t => t.IsEnum)

            .Distinct()

            .ToDictionary(t => t.Name, t =>

                  Enum.GetNames(t)

                      .Zip(Enum.GetValues(t).Cast<int>(), (Key, Value) => new { Key, Value })

                      .ToDictionary(kvp => kvp.Key, kvp => kvp.Value));

    }

    // These should not appear in the output

    enum VagueLocation { Nowhere, Here, There, Eveywhere };

    enum Outcome { Win = 1, Loss = -1, Tie = 0 };

​

    // These should appear in the output because they are used in Model1 and/or Model2

    enum Color { Black, Cyan, Magenta, Yellow };

    enum Size { Tiny, Small, Normal, Big, Huge };

    enum Rating { WorstEver, Terrible, Bad, SubPar, Meh, Passable, Good, Great, Stellar };

​

    class Model1

    {

        public int Id { get; set; }

        public string Name { get; set; }

        public Size Size { get; set; }

        public Color Color { get; set; }

        public double Weight { get; set; }

    }

    class Model2

    {

        public Rating Rating { get; set; }

        public Size Size { get; set; }

        public int Number { get; set; }

    }

}

​