Return a single JSON from SQL Server and map it into a custom object

stackoverflow-dapper-50091943.cs

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using Dapper;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace stackoverflow_dapper_50091943
{
    public class City
    {
        public int CityId;
        public string CityName;
    }

    public class Country {
        public int CountryId;
        public string CountryName;
        public List<City> Cities = new List<City>();
    }

    public class Continent 
    {
        public int ContinentId;
        public string ContinentName;
        public List<Country> Countries = new List<Country>();
    }

    class Program
    {
         public class ContinentTypeHandler : SqlMapper.TypeHandler<List<Continent>>
        {
            // Handles how data is deserialized into object
            public override List<Continent> Parse(object value)
            {
                return JsonConvert.DeserializeObject<List<Continent>>(value.ToString());
            }

            // Handles how data is saved into the database
            public override void SetValue(IDbDataParameter parameter, List<Continent> value)
            {
                parameter.Value = null;
            }
        }

        static void Main(string[] args)
        {
            SqlMapper.ResetTypeHandlers();
            SqlMapper.AddTypeHandler(new ContinentTypeHandler());

            using (SqlConnection conn = new SqlConnection(@"Data Source=(LocalDB)\MSSQLLocalDB; Initial Catalog=tempdb;"))
            {
                var result = conn.QuerySingle<List<Continent>>("dbo.GetContinentsDetail", commandType: CommandType.StoredProcedure);
                
                result.ForEach(c => {
                    Console.WriteLine(JsonConvert.SerializeObject(c));
                    Console.WriteLine();
                    });                
            }
        }
    }
}