async void pivotGridControl1_CellClick(object sender, PivotCellEventArgs e)
        {
            PivotGridControl pivot = sender as PivotGridControl;

            if (dForm.IsDisposed)
            {
                LoadDrillDownForm();
            }

            //Check whether an asynchronous operation is in progress.
            if (!pivot.IsAsyncInProgress)
            {
                // Get the record set associated with the clicked cell.
                dForm.DataSource = await pivot.CreateDrillDownDataSourceAsync(e.ColumnIndex, e.RowIndex, 25, new List <string> {
                    "ProductName", "Quantity"
                });
            }
        }