GridColumnSummary.Type Property

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

Namespace: DevExpress.Maui.DataGrid

Assembly: DevExpress.Maui.DataGrid.dll

NuGet Package: DevExpress.Maui.DataGrid

Declaration

public DataSummaryType Type { get; set; }

Property Value

Type
DataSummaryType

Available values:

Name	Description
None	A summary is not calculated.
Sum	The sum of values in a group of rows or an entire column.
Min	The minimum value in a group of rows or an entire column.
Max	The maximum value in a group of rows or an entire column.
Count	The number of records in a group or an entire column.
Average	The average value of a group of rows or an entire column.
Custom	Specifies whether data summaries should be calculated according to a custom rule specified in the DataGridView.CustomSummary event handler.

Remarks

Use the Type property to specify the aggregate function that should be used to calculate the summary value. There are five predefined aggregate functions for grid data summaries: Sum, Min, Max, Average and Count.

To implement and apply a custom aggregate function, set the Type property to Custom and handle the DataGridView.CustomSummary event.

Example

The following example uses predefined aggregate functions (Max and Sum) and a custom rule to calculate group and total summaries for a grid that displays orders grouped by dates.

Set up the following summaries:

• A group summary to display the maximum Total value for each group of orders.
• A total summary to calculate the sum of values in the Total column.
• A custom total summary to count the number of orders with the false value in the Shipped column.

XAML

<dxg:DataGridView x:Name="grid" ItemsSource="{Binding Orders}" 
                  CustomSummary="grid_CalculateCustomSummary">
    <!-- ... -->
    <dxg:DataGridView.GroupSummaries>
        <dxg:GridColumnSummary FieldName="Total" Type="Max"/>
    </dxg:DataGridView.GroupSummaries>

    <dxg:DataGridView.TotalSummaries>
        <dxg:GridColumnSummary FieldName="Total" Type="Sum" 
                               DisplayFormat="Total: {0:C0}"/>
        <dxg:GridColumnSummary FieldName="Shipped" Type="Custom" 
                               DisplayFormat="Not Shipped: {0}"/>
    </dxg:DataGridView.TotalSummaries>
</dxg:DataGridView>

C#

int count;
// ...

void grid_CalculateCustomSummary(object sender, DevExpress.Data.CustomSummaryEventArgs e) {
    if (e.FieldName.ToString () == "Shipped")
        if (e.IsTotalSummary){
            if (e.SummaryProcess == CustomSummaryProcess.Start) {
                count = 0;
            }
            if (e.SummaryProcess == CustomSummaryProcess.Calculate) {
                if (!(bool)e.FieldValue)
                    count++;
                e.TotalValue = count;
            }
        }
}