SummaryItemBase.SummaryType Property

Gets or sets the aggregate function type. This is a dependency property.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v24.2.Core.dll

NuGet Package: DevExpress.Wpf.Grid.Core

Declaration

C#

public SummaryItemType SummaryType { get; set; }

VB.NET

Public Property SummaryType As SummaryItemType

Property Value

Type	Description
SummaryItemType	A SummaryItemType enumeration value that specifies the aggregate function type.

Available values:

Name	Description
Sum	The sum of all values in a column.
Min	The minimum value in a column.
Max	The maximum value in a column.
Count	The record count.
Average	The average value of a column.
Custom	Specifies whether calculations should be performed manually using a specially designed event.
None	Disables summary value calculation.

Remarks

There are five predefined aggregate functions. These are: Sum, Min, Max, Average and Count. To implement your own aggregate function, set the SummaryType property to SummaryItemType.Custom, and handle the GridControl.CustomSummary event.

Average and Sum summaries are only calculated for columns that contain numerical data.

Example

The following example demonstrates how to use custom summaries to count the total number of empty cells in the specified grid column:

View Example: How to Use Custom Summaries

MainWindow.xaml

<dxg:GridControl x:Name="grid"
                 CustomSummary="OnCustomSummary">
    <dxg:GridControl.Columns>
        <dxg:GridColumn FieldName="Text" GroupIndex="0" />
        <dxg:GridColumn FieldName="Number" />
    </dxg:GridControl.Columns>
    <dxg:GridControl.View>
        <dxg:TableView x:Name="view"
                       AutoWidth="True"
                       NavigationStyle="Cell"
                       TotalSummaryPosition="Bottom" />
    </dxg:GridControl.View>
    <dxg:GridControl.TotalSummary>
        <dxg:GridSummaryItem DisplayFormat="Total empty cells count: {0}"
                             FieldName="Number"
                             SummaryType="Custom" />
    </dxg:GridControl.TotalSummary>
    <dxg:GridControl.GroupSummary>
        <dxg:GridSummaryItem DisplayFormat="Group empty cells count: {0}"
                             FieldName="Number"
                             SummaryType="Custom" />
    </dxg:GridControl.GroupSummary>
</dxg:GridControl>

MainWindow.xaml.cs

void OnCustomSummary(object sender, CustomSummaryEventArgs e) {
    if(((GridSummaryItem)e.Item).FieldName != "Number")
        return;
    if(e.SummaryProcess == CustomSummaryProcess.Start) {
        e.TotalValue = 0;
    }
    if(e.SummaryProcess == CustomSummaryProcess.Calculate) {
        if(IsEmptyCell(e.FieldValue))
            e.TotalValue = (int)e.TotalValue + 1;
    }
}
bool IsEmptyCell(object fieldValue) {
    return !((int?)fieldValue).HasValue;
}

MainWindow.xaml.vb

Private Sub OnCustomSummary(ByVal sender As Object, ByVal e As CustomSummaryEventArgs)
    If Not Equals(CType(e.Item, GridSummaryItem).FieldName, "Number") Then Return
    If e.SummaryProcess = CustomSummaryProcess.Start Then
        e.TotalValue = 0
    End If

    If e.SummaryProcess = CustomSummaryProcess.Calculate Then
        If IsEmptyCell(e.FieldValue) Then e.TotalValue = CInt(e.TotalValue) + 1
    End If
End Sub

Private Function IsEmptyCell(ByVal fieldValue As Object) As Boolean
    Return Not CType(fieldValue, Integer?).HasValue
End Function

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the SummaryType property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

XAML

wpf-data-grid-process-frequent-data-updates/CS/ChunkAndOptSummariesExample/MainWindow.xaml#L18

<dxg:GridControl.TotalSummary>
    <dxg:GridSummaryItem SummaryType="Count" FieldName="Name" DisplayFormat="Total count: {0:N0}"/>
</dxg:GridControl.TotalSummary>

wpf-data-grid-implement-crud-operations/CS/CodeBehind/EFCore/LocalData/MainWindow.xaml#L38

<dxg:GridControl.TotalSummary>
    <dxg:GridSummaryItem SummaryType="Count" Alignment="Right" />
</dxg:GridControl.TotalSummary>

how-to-bind-wpf-grid-to-data/CS/CodeBehind/EFCore/LocalData/MainWindow.xaml#L17

<dxg:GridControl.TotalSummary>
    <dxg:GridSummaryItem SummaryType="Count" Alignment="Right" />
</dxg:GridControl.TotalSummary>

wpf-data-grid-display-group-summaries/CS/DisplayGroupSummaries_CodeBehind/MainWindow.xaml#L19

<dxg:GridControl.GroupSummary>
    <dxg:GridSummaryItem FieldName="Age" SummaryType="Min"/>
    <dxg:GridSummaryItem FieldName="Age" SummaryType="Max"/>

wpf-data-grid-bind-to-pagedasyncsource/CS/PagedAsyncSourceSample/MainWindow.xaml#L30

<dxg:GridControl.TotalSummary>
    <dxg:GridSummaryItem SummaryType="Count" Alignment="Right"/>
    <dxg:GridSummaryItem SummaryType="Max" FieldName="Created" DisplayFormat="{}Last created: {0}" Alignment="Right"/>