Connection SQL using C#

using System;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;

namespace PruebaDB
{
    class Program
    {
        static void Main(string[] args)
        {
            var arrayIds = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

            Console.WriteLine("============== INSERTANDO REGISTROS EN LA BD =============");


            string name = "John {0}", lastname = "Doe {0}", address = "Dirección {0}.";
            foreach (var id in arrayIds)
            {
                var item = new Item()
                {
                    Name = string.Format(name, id),
                    LastName = string.Format(lastname, id),
                    Address = (id%2) > 0 ? string.Format(address,id):null
                };
                AddItem(item);
            }
            Console.WriteLine("...Listo.");


            Console.WriteLine("\n============== LEYENDO DATOS DE LA BD =============");

            foreach (var id in arrayIds)
            {
                var item = GetItemById(id);
                if(item != null)
                {
                    Console.WriteLine("Id:{0} | Name: {1} | LastName: {2} | Address:{3}",
                                        item.Id, item.Name, item.LastName, item.Address);
                }

            }
            Console.WriteLine("...Listo.");
            Console.WriteLine("\n============= Limpiando Tabla (truncate) =============");

            TruncateTable();

            Console.WriteLine("...Listo.");


            Console.ReadKey();
        }

        private static void AddItem(Item item)
        {
            if (item == null) throw new ArgumentNullException("item");

            try
            {
                var connString = ConfigurationManager.ConnectionStrings["TESTDBConnection"].ConnectionString;
                var sqlCommand = "INSERT INTO Item(Name, LastName, Address) VALUES(@Name, @LastName, @Address)";

                using (var connection = new SqlConnection(connString))
                {
                    using (var command = new SqlCommand(sqlCommand, connection))
                    {
                        command.Parameters.Add("@Name", SqlDbType.NVarChar).Value = item.Name;
                        command.Parameters.Add("@LastName", SqlDbType.NVarChar).Value = item.LastName;
                        if(string.IsNullOrEmpty(item.Address))
                            command.Parameters.Add("@Address", SqlDbType.NVarChar).Value = DBNull.Value;
                        else
                            command.Parameters.Add("@Address", SqlDbType.NVarChar).Value = item.Address;

                        connection.Open();
                        command.ExecuteNonQuery();
                    }
                }

            }
            catch
            {
                throw;
            }
        }

        //EJECUTANDO A UN STORE PROCEDURE
        private static Item GetItemById(int itemId)
        {
            try
            {
                Item retrievedItem = null;

                var connString = ConfigurationManager.ConnectionStrings["TESTDBConnection"].ConnectionString;
                var sqlCommand = "sp_GetItemById";

                using (var connection = new SqlConnection(connString))
                {
                    using (var command = new SqlCommand(sqlCommand, connection))
                    {
                        command.CommandType = CommandType.StoredProcedure;
                        command.Parameters.Add("@ItemId", SqlDbType.Int).Value = itemId;

                        connection.Open();
                        var reader = command.ExecuteReader();

                        if (!reader.HasRows)
                            return retrievedItem;
                        else
                            retrievedItem = new Item();

                        while (reader.Read())
                        {
                            retrievedItem.Id = Convert.ToInt32(reader["Id"]);
                            retrievedItem.Name = reader["Name"] as string;
                            retrievedItem.LastName = reader["LastName"] as string;
                            retrievedItem.Address = reader["Address"] as string;
                        }
                        return retrievedItem;
                    }
                }

            }
            catch
            {
                throw;
            }
        }


        private static void TruncateTable()
        {
            try
            {
                var connString = ConfigurationManager.ConnectionStrings["TESTDBConnection"].ConnectionString;
                var sqlCommand = "TRUNCATE TABLE Item";

                using (var connection = new SqlConnection(connString))
                {
                    using (var command = new SqlCommand(sqlCommand, connection))
                    {
                        connection.Open();
                        command.ExecuteNonQuery();
                    }
                }

            }
            catch
            {
                throw;
            }
        }
    }//program.cs

    public class Item
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string LastName { get; set; }
        public string Address { get; set; }

    }
}