ASPxPivotGrid.CustomSummary Event
Enables summary values to be calculated manually.
Namespace: DevExpress.Web.ASPxPivotGrid
Assembly: DevExpress.Web.ASPxPivotGrid.v19.1.dll
Declaration
Event Data
The CustomSummary event's data class is PivotGridCustomSummaryEventArgs. The following properties provide information specific to this event:
| Property | Description |
|---|---|
| ColumnField | Gets the column field that corresponds to the current cell. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
| ColumnFieldValue | Gets the value of the column field that corresponds to the current cell. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
| CustomValue | Gets or sets a custom summary value. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
| DataField | Gets the data field against which the summary is calculated. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
| FieldName | Gets the name of the data field against which the summary is calculated. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
| RowField | Gets the row field that corresponds to the current cell. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
| RowFieldValue | Gets the value of the row field that corresponds to the current cell. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
| SummaryValue | Gets an object that contains the values of the predefined summaries which are calculated for the current cell. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
The event data class exposes the following methods:
| Method | Description |
|---|---|
| CreateDrillDownDataSource() | Returns data records associated with the current cell. Inherited from PivotGridCustomSummaryEventArgsBase<T>. |
Remarks
The ASPxPivotGrid calculates summaries against data fields. A field’s PivotGridFieldBase.SummaryType property specifies the type of summary function. The control automatically calculates all the predefined summary functions (see the PivotSummaryType topic for a list of the available functions) and it allows custom summaries to be calculated manually using the CustomSummary event.
To calculate a custom summary for a specific data field, set its PivotGridFieldBase.SummaryType property to PivotSummaryType.Custom. In this instance, the CustomSummary event fires for each cell that corresponds to this data field. Use the PivotGridCustomSummaryEventArgsBase<T>.DataField property to identify the data field.
To identify the kind of a processed cell, you can use the PivotGridCustomSummaryEventArgsBase<T>.ColumnField and PivotGridCustomSummaryEventArgsBase<T>.RowField properties.
- If ColumnField or RowField is null, it means that the processed cell is a Grand Total.
- If both ColumnField and RowField are last fields in the corresponding area, this means that this is an ordinary cell.
- In other cases, this is a Total cell.
For example, you can handle the CustomSummary event to calculate custom summaries against multiple fields, particular records, etc. Use the PivotGridCustomSummaryEventArgsBase<T>.CreateDrillDownDataSource method to get a list of records that correspond to the processed cell. This list can then be traversed to calculate a custom summary. The custom summary value should be assigned to the PivotGridCustomSummaryEventArgsBase<T>.CustomValue property.
The ASPxPivotGrid calculates all the predefined summaries (AVERAGE, MIN, MAX, SUM, etc.) for each cell. The calculated summaries can be accessed using the PivotGridCustomSummaryEventArgsBase<T>.SummaryValue property and used in custom summary calculations.
Example
The following example shows how to calculate a custom summary.Assume that the ASPxPivotGrid control is bound to an "Invoices" table, which contains invoices information (product name, extended price, salesperson, etc). A field that displays the ratio of units cost over $50 is to be added.In this example, a custom summary is calculated against the "Unit Price" field. Its PivotGridCustomTotalBase.SummaryType property is set to PivotSummaryType.Custom and the caption to "Percentage of units cost over $50". The PivotGridControl.CustomSummary event is handled to only count those records whose total sum exceeds $50. The ratio of these records to all the records is a custom summary value and, therefore, is assigned to the PivotGridCustomSummaryEventArgsBase.CustomValue parameter.
Note
A complete sample project is available at https://github.com/DevExpress-Examples/how-to-implement-custom-summary-e1877
using System.Web.UI;
using DevExpress.Web.ASPxPivotGrid;
using DevExpress.XtraPivotGrid;
namespace ASPxPivotGrid_CustomSummary {
public partial class _Default : Page {
static int minSum = 500;
protected void ASPxPivotGrid1_CustomSummary(object sender,
PivotGridCustomSummaryEventArgs e) {
if (e.DataField != fieldExtendedPrice) return;
// A variable which counts the number of orders whose sum exceeds $500.
int order500Count = 0;
// Get the record set corresponding to the current cell.
PivotDrillDownDataSource ds = e.CreateDrillDownDataSource();
// Iterate through the records and count the orders.
for (int i = 0; i < ds.RowCount; i++) {
PivotDrillDownDataRow row = ds[i];
// Get the order's total sum.
decimal orderSum = (decimal)row[fieldExtendedPrice];
if (orderSum >= minSum) order500Count++;
}
// Calculate the percentage.
if (ds.RowCount > 0) {
e.CustomValue = (decimal)order500Count / ds.RowCount;
}
}
}
}