private void pivotGridControlStampe_CustomSummary(object sender, DevExpress.XtraPivotGrid.PivotGridCustomSummaryEventArgs e)
        {
            string name = e.DataField.FieldName; // Stampa.Vendita.Oid;

            if (e.DataField.SummaryType == DevExpress.Data.PivotGrid.PivotSummaryType.Custom)
            {
                if (name == "Vendita.Oid")
                {
                    IList     list = e.CreateDrillDownDataSource();
                    Hashtable ht   = new Hashtable();
                    for (int i = 0; i < list.Count; i++)
                    {
                        DevExpress.XtraPivotGrid.PivotDrillDownDataRow row = list[i] as DevExpress.XtraPivotGrid.PivotDrillDownDataRow;

                        object v = row[name];

                        if (v != null && v != DBNull.Value)
                        {
                            ht[v] = null;
                        }
                    }

                    e.CustomValue = ht.Count;
                }
            }
        }
        private void pivotGridControl1_CustomSummary(object sender, DevExpress.Xpf.PivotGrid.PivotCustomSummaryEventArgs e)
        {
            string name = e.DataField.FieldName;

            IList     list = e.CreateDrillDownDataSource();
            Hashtable ht   = new Hashtable();

            for (int i = 0; i < list.Count; i++)
            {
                DevExpress.XtraPivotGrid.PivotDrillDownDataRow row = list[i] as DevExpress.XtraPivotGrid.PivotDrillDownDataRow;
                object v = row[name];
                if (v != null && v != DBNull.Value)
                {
                    ht[v] = null;
                }
            }
            e.CustomValue = ht.Count;
        }