public static User getUser(string login)
        {
            SqlConnection myConnection = null;

            ConnectionStringSettings connectionSetting = getConnectionSettings("sql01");
            string connectionStr = "Data Source = " + connectionSetting.ConnectionString;

            User _user = new User();
            //SqlDataAdapter _sqlDataAdapter = null;
            DataTable userTable = new DataTable();

            try
            {
                myConnection = new SqlConnection(connectionStr);
                myConnection.Open();

                SqlCommand cmd = new SqlCommand("SELECT * FROM Users WHERE login=@login", myConnection);
                //SqlParameter param = new SqlParameter();
                cmd.Parameters.Add(new SqlParameter("@login", login));
                //cmd.Parameters.Add(new SqlParameter("@login", SqlDbType.VarChar, 100,login));

                SqlDataAdapter _sqlDataAdapter = new SqlDataAdapter(cmd);
                // _sqlDataAdapter.InsertCommand = cmd;
                _sqlDataAdapter.Fill(userTable);

                DataRow _dataRow = userTable.Rows[0];

                _user = convert_DataRowToUser(_dataRow);

                return _user;
            }
            finally
            {
                // close connection
                if (myConnection != null)
                {
                    myConnection.Close();
                }
            }
        }
        private static User convert_DataRowToUser(DataRow _dataRowUser)
        {
            User itemUser = new User();

            itemUser.FirstName = _dataRowUser.Field<string>("first_name");
            itemUser.Hash = _dataRowUser.Field<byte[]>("hash");
            itemUser.LastName = _dataRowUser.Field<string>("last_name");
            itemUser.Login = _dataRowUser.Field<string>("login");

            //itemUser.Parent_User_id = null;

            itemUser.Salt1 = _dataRowUser.Field<byte[]>("salt1");
            itemUser.Salt2 = _dataRowUser.Field<byte[]>("salt2");
            itemUser.User_ID = _dataRowUser.Field<Guid>("user_id");

            return itemUser;
        }