ChartElementSelectionChangedEventArgs Class

Contains data for the SelectionChanged event.

Namespace: DevExpress.WinUI.Charts

Assembly: DevExpress.WinUI.Charts.v23.2.dll

NuGet Package: DevExpress.WinUI

Declaration

C#

public class ChartElementSelectionChangedEventArgs :
    ElementSelectionChangedEventArgs

VB.NET

Public Class ChartElementSelectionChangedEventArgs
    Inherits ElementSelectionChangedEventArgs

Related API Members

ChartElementSelectionChangedEventArgs is the data class for the following events:

• ChartBase.SelectionChanged

Remarks

The chart creates an instance of the ChartElementSelectionChangedEventArgs class with the appropriate settings and passes it to the SelectionChanged event handler.

The ChartBase.SelectionChanged event occurs when a user selects or deselects series points. Use the e.Selection property to obtain selected items. The following example calculates the total area of selected countries:

C#

private void chartOfCountriesArea_SelectionChanged(object sender, ChartElementSelectionChangedEventArgs e) {
    double totalArea = 0;
    foreach (CountryStatisticInfo point in e.Selection) {
        totalArea += point.AreaMSqrKilometers;
    }
    selectedItemsText.Text = String.Format("Total area of ​​selected countries: {0}", totalArea);
}

VB.NET

Private Sub chartOfCountriesArea_SelectionChanged(ByVal sender As Object, ByVal e As ChartElementSelectionChangedEventArgs)
    Dim totalArea As Double = 0
    For Each point As CountryStatisticInfo In e.Selection
        totalArea += point.AreaMSqrKilometers
    Next
    selectedItemsText.Text = String.Format("Total area of ​​selected countries: {0}", totalArea)
End Sub

Use the e.ChangedElement property to get the series point whose selection state is changed. The e.IsSelected property returns this selection state. The following code calls a custom UpdateStatistics method for the last selected series point:

C#

private void chartOfCountriesArea_SelectionChanged(object sender, ChartElementSelectionChangedEventArgs e) {
    selectedItemsText.Text = String.Format("Total area of ​​selected countries: {0}", totalArea);
    if (e.IsSelected) {
        UpdateStatistics((CountryStatisticInfo)e.ChangedElement);
    }
}

VB.NET

Private Sub chartOfCountriesArea_SelectionChanged(ByVal sender As Object, ByVal e As ChartElementSelectionChangedEventArgs)
    selectedItemsText.Text = String.Format("Total area of ​​selected countries: {0}", totalArea)
    If e.IsSelected Then
        UpdateStatistics(CType(e.ChangedElement, CountryStatisticInfo))
    End If
End Sub

Inheritance

Object

EventArgs

ElementSelectionChangedEventArgs

ChartElementSelectionChangedEventArgs