public List <TarifModel> GetTarifByAgent(string login)
        {
            List <TarifModel> tarifs = new List <TarifModel>();

            using (SqlConnection conn = new SqlConnection(_connectionStringCabinet))
            {
                conn.Open();

                SqlCommand cmd = new SqlCommand("dbo.GetTarifByAgent", conn);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddWithValue("@login", login);
                SqlDataReader reader = cmd.ExecuteReader();

                while (reader.Read())
                {
                    TarifModel tarif = new TarifModel();
                    tarif.Id         = reader["Id"] != DBNull.Value ? Convert.ToInt32(reader["Id"]) : 0;
                    tarif.Name       = reader["Name"] != DBNull.Value ? Convert.ToString(reader["Name"]) : string.Empty;
                    tarif.QueryCount = reader["QueryCount"] != DBNull.Value ? Convert.ToInt32(reader["QueryCount"]) : 0;
                    tarif.Sum        = reader["Sum"] != DBNull.Value ? Convert.ToInt32(reader["Sum"]) : 0;
                    tarifs.Add(tarif);
                }
            }
            return(tarifs);
        }
        public bool DeleteTarif(TarifModel tarif)
        {
            using (SqlConnection conn = new SqlConnection(_connectionStringAdmin))
            {
                conn.Open();

                SqlCommand cmd = new SqlCommand("dbo.DeleteTarif", conn);
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddWithValue("@Id", tarif.Id);
                return(Convert.ToBoolean(cmd.ExecuteScalar()));
            }
        }