namespace Test
{
    public class Contract
    {
        public uint Id { get; set; }
        public string Number { get; set; }
        public DateTime DateStart { get; set; }
    }

	public class GenericObj
    {
        public Dictionary<string, object> PropertiesNameValueCollection { get; set; } = new Dictionary<string, object>();
    }

	public class MySqlService
    {
        private string ConStr;
        public MySqlService(string conStr)
        {
            ConStr = conStr;
        }

        public List<GenericObj> ExecuteReader(string sql)
        {
            var list = new List<GenericObj>();
            using (var con = new MySqlConnection(ConStr))
            using (var cmd = new MySqlCommand(sql, con))
            {
                con.Open();
                var reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    var count = reader.FieldCount;
                    var obj = new GenericObj();
                    for (int i = 0; i < count; i++)
                    {
                        obj.PropertiesNameValueCollection.Add(reader.GetName(i), reader.GetValue(i));
                    }
                    list.Add(obj);
                }
            }
            return list;
        }
    }

    public class Resolver<T>
    {
        public T Resolve(GenericObj obj)
        {
            var type = typeof(T);
            T specificObj = (T)Activator.CreateInstance(type);
            foreach(var field in obj.PropertiesNameValueCollection)
            {
                type.GetProperty(field.Key).SetValue(specificObj, field.Value);
            }
            return specificObj;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            var service = new MySqlService("constr");
            var result = service.ExecuteReader("SELECT mai_id as Id, mai_no_d as Number, mai_date_start as DateStart FROM main");

            var list = new List<Contract>();
            var resolver = new Resolver<Contract>();
            foreach (var genObj in result)
            {
                list.Add(resolver.Resolve(genObj));
            }
        }
    }
}