WPF DEV gridcontrol 自定义计算列(TotalSummary)

　　　　　/// <summary>
        /// 自定义计算列
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void user_GridControl_CustomSummary(object sender, CustomSummaryEventArgs e)
        {
            try
            {foreach (var item in dic)
                    if (item.Key == ((GridSummaryItem)e.Item).FieldName)
                        if (e.IsTotalSummary)
                            if (e.SummaryProcess == CustomSummaryProcess.Start)
                                e.TotalValue = item.Value;
            }
            catch (Exception ex)
            {
            }
        }

//生成数据的时候
user_GridControl.TotalSummary.Clear();
foreach (DataColumn item in source.Columns)
    user_GridControl.TotalSummary.Add(new GridSummaryItem()
      {
        SummaryType = DevExpress.Data.SummaryItemType.Custom,
        FieldName = item.ColumnName,
        DisplayFormat = item.ColumnName + "的和:{0}"
      });

XAML

<dxg:GridControl x:Name="user_GridControl"
                 CustomSummary="user_GridControl_CustomSummary"
                 FilterChanged="user_GridControl_FilterChanged"
                 AutoExpandAllGroups="True"
                 AutoPopulateColumns="True"
                 ScrollViewer.CanContentScroll="True"
                 AllowColumnMRUFilterList="True"
                 dx:ScrollBarExtensions.ScrollBarMode="TouchOverlap"
                 Margin="5" Grid.Row="1">
            <dxg:GridControl.GroupSummary>
                <dxg:GridSummaryItem SummaryType="Count" />
            </dxg:GridControl.GroupSummary>
            <dxg:GridControl.View>
                <dxg:TableView AllowEditing="False"
                               BestFitMode="VisibleRows"
                               WheelScrollLines="1"
                               RowMinHeight="30" x:Name="SummaryTable"
                               AllowMoveColumnToDropArea="False" ShowGroupPanel="False"
                               AllowGrouping="True"
                               AllowBandMoving="True" AllowResizing="True"
                               AllowBestFit="True"
                               ShowSearchPanelMode="Always" 

                               ShowIndicator="True"
                               ShowAutoFilterRow="True"
                               NavigationStyle="Row" RowAnimationKind="Custom"
                               WaitIndicatorType="Default"
                               ShowFixedTotalSummary="False" AllowScrollAnimation="True"
                               AllowFixedGroups="True" ColumnFilterPopupMode="Default"
                               AllowChangeBandParent="False"
                               AllowPerPixelScrolling="True"
                               ShowTotalSummary="True"
                               ShowFilterPanelMode="ShowAlways"
                               >
                    </dxg:TableView>
                </dxg:GridControl.View>
            </dxg:GridControl>