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CustomDrawAxisLabelEventArgs.Item Property

corelibraries-devexpress-dot-xtracharts-dot-customdrawaxislabeleventargs.md

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CustomDrawAxisLabelEventArgs.Item Property

Provides access to individual axis label items.

Namespace : DevExpress.XtraCharts

Assembly : DevExpress.XtraCharts.v25.2.dll

NuGet Package : DevExpress.Charts

Declaration

csharp
public AxisLabelItemBase Item { get; }
vb
Public ReadOnly Property Item As AxisLabelItemBase

Property Value

TypeDescription
AxisLabelItemBase

A AxisLabelItem object which represents the axis label item.

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Remarks

An axis label item is the specific instance of the AxisLabelItem class, obtained in the ChartControl.CustomDrawAxisLabel (or WebChartControl.CustomDrawAxisLabel) event handler.

In this event, you can use the Item property to access and modify both the value and appearance of an individual axis label item, and also access the associated axis itself.

For more information, refer to Axis Labels.

Example

Apart from the capability to customize the overall appearance of axis labels, you can obtain individual axis labels at runtime. Then, it’s possible to apply all the options available for axis labels to them, individually. For example, based on some criteria (e.g. an axis value threshold), you can apply different formatting to axis labels.

For this, the special ChartControl.CustomDrawAxisLabel event is introduced. Handle it to obtain axis labels.

Note

For the WebChartControl you should handle its WebChartControl.CustomDrawSeries event to implement this task.

The following code demonstrates one possible implementation of this capability.

csharp
private void chartControl1_CustomDrawAxisLabel(object sender, CustomDrawAxisLabelEventArgs e) {
    AxisBase axis = e.Item.Axis;
    if (axis is AxisY || axis is AxisY3D || axis is RadarAxisY) {
        double axisValue = (double)e.Item.AxisValue;
        if (axisValue < 0) {
            e.Item.TextColor = Color.Red;
        }
        else if (axisValue > 0) {
            e.Item.Text = "+" + e.Item.Text;
            e.Item.TextColor = Color.Green;
        }
        else if (axisValue == 0) {
            e.Item.Text = "Zero";
        }
    }
}
vb
Private Sub chartControl1_CustomDrawAxisLabel(sender As Object, e As CustomDrawAxisLabelEventArgs)
   Dim axis As AxisBase = e.Item.Axis
   If TypeOf axis Is AxisY Or TypeOf axis Is AxisY3D Or TypeOf axis Is RadarAxisY Then
      Dim axisValue As Double = CDbl(e.Item.AxisValue)
      If axisValue < 0 Then
         e.Item.TextColor = Color.Red
      Else
         If axisValue > 0 Then
            e.Item.Text = "+" + e.Item.Text
            e.Item.TextColor = Color.Green
         Else
            If axisValue = 0 Then
               e.Item.Text = "Zero"
            End If
         End If
      End If
   End If
End Sub

See Also

CustomDrawAxisLabelEventArgs Class

CustomDrawAxisLabelEventArgs Members

DevExpress.XtraCharts Namespace