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}"
});

<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>