private void  func_update()
    {
        
            SqlConnection conn = new SqlConnection(Form_Export.connect);
            conn.Open();
            SqlCommand myCommand = conn.CreateCommand();
            //Создаем транзакцию   
           // myCommand.Transaction = conn.BeginTransaction(System.Data.IsolationLevel.Serializable);
            try
           {
            string index_c = comboBox_Nomenclature.SelectedValue.ToString();
            myCommand.CommandText = @"update  Basises set Basis=@Basis, Nomenclature=@Nomenclature Where Id=" + Id_Basis;
            myCommand.Parameters.Add("@Basis", SqlDbType.VarChar, 25);
            myCommand.Parameters["@Basis"].Value = textBox_basis.Text.Trim();
            myCommand.Parameters.Add("@Nomenclature", SqlDbType.VarChar, 25);
            myCommand.Parameters["@Nomenclature"].Value = index_c;
            myCommand.ExecuteNonQuery();
            myCommand.CommandText = @"delete from [dbo].[Metrics] where  basis=" + Id_Basis;
            myCommand.ExecuteNonQuery();

            myCommand.CommandText = @"Insert into [dbo].[Metrics]  (basis,parameter,value)
                                       values
                                      (@Basis,@Parameter,@Value)";
                  
            myCommand = new SqlCommand(myCommand.CommandText, conn);
            myCommand.Parameters.Add("@Basis", SqlDbType.Int);
            myCommand.Parameters.Add("@Parameter", SqlDbType.VarChar, 25);
            myCommand.Parameters.Add("@Value", SqlDbType.Decimal).Value = DBNull.Value;
            for (int i = 0; i < GridView_Metrics.RowCount; i++)
            {
              {
                    myCommand.Parameters["@Basis"].Value = GridView_Metrics["basis", i].Value.ToString();
                    myCommand.Parameters["@Parameter"].Value = GridView_Metrics["metric", i].Value.ToString();
                    
                   if (GridView_Metrics["value", i].Value.ToString().Length > 0)
                    {  myCommand.Parameters["@Value"].Value = Convert.ToDecimal(GridView_Metrics["value", i].Value.ToString()); }
                    else
                    {  myCommand.Parameters["@Value"].Value = DBNull.Value; }
                
   
                }
              myCommand.ExecuteNonQuery();
          }
        //    myCommand.Transaction.Commit();   
          }
        catch (Exception ex)
        {
            //Отклоняем транзакцию  
         //   myCommand.Transaction.Rollback();
            MessageBox.Show(ex.Message);
        }
        finally
        { conn.Close(); }

      }