How to: Determine a Chart Element the Mouse Pointer Hovers Over

Apr 04, 2025
2 minutes to read

The following example handles the ChartControl.MouseMove event to identify the chart element under the mouse pointer and display its name in the form’s caption.

Note

Turn on the ChartControl.RuntimeHitTesting option to enable hit testing.

C#
VB.NET

csharp

using DevExpress.XtraCharts;
using System.Windows.Forms;

namespace DXApplication {
    public partial class Form1 : DevExpress.XtraEditors.XtraForm {
        public Form1() {
            InitializeComponent();
            chartControl1.MouseMove += ChartControl1_MouseMove;
            chartControl1.RuntimeHitTesting = true;
        }

        void ChartControl1_MouseMove(object sender, MouseEventArgs e) {
            ChartHitInfo hi = chartControl1.CalcHitInfo(new System.Drawing.Point(e.X, e.Y));
            this.Text = hi.HitTest.ToString();
        }
    }
}

Imports DevExpress.XtraCharts
Imports System.Windows.Forms

Namespace DXApplication
    Public Partial Class Form1
        Inherits DevExpress.XtraEditors.XtraForm

        Public Sub New()
            InitializeComponent()
            AddHandler chartControl1.MouseMove, AddressOf ChartControl1_MouseMove
            chartControl1.RuntimeHitTesting = True
        End Sub

        Private Sub ChartControl1_MouseMove(sender As Object, e As MouseEventArgs)
            Dim hi As ChartHitInfo = chartControl1.CalcHitInfo(New System.Drawing.Point(e.X, e.Y))
            Me.Text = hi.HitTest.ToString()
        End Sub
    End Class
End Namespace

Identify the Series Name on Mouse Move

The following example obtains the name of the series under the mouse pointer and displays it in the form’s caption:

csharp

using DevExpress.XtraCharts;
using System.Windows.Forms;

namespace DXApplication {
    public partial class Form1 : DevExpress.XtraEditors.XtraForm {
        public Form1() {
            InitializeComponent();
            chartControl1.MouseMove += ChartControl1_MouseMove;
            chartControl1.RuntimeHitTesting = true;
        }

        void ChartControl1_MouseMove(object sender, MouseEventArgs e) {
            ChartHitInfo hi = chartControl1.CalcHitInfo(new System.Drawing.Point(e.X, e.Y));
            if(hi.HitTest == ChartHitTest.Series){
                this.Text = ((Series)hi.Series).Name;
            }
        }
    }
}