Imports System.Windows.Forms.DataVisualization.Charting
 
Public Class frmChart2
 
    Dim WithEvents chart1 As New Chart With _
           {.Parent = Me, .Top = 50}
 
    Dim WithEvents nud As New NumericUpDown With _
           {.Parent = Me}
 
 
    Private Sub frmChart2_Load(sender As System.Object, _
        e As System.EventArgs) Handles MyBase.Load
 
        Dim x() As Double = {5, 6, 7, 8, 9, 10, 6, 6}
        Dim y() As Double = {100, 110, 120, 130, 140, 150, 80, 120}
        Dim y2() As Double = {150, 90, 100, 160, 100, 90, 90, 130}
        Dim x2() As Double = {5.5, 6.5, 7.5, 8.5, 9.5, 10.5, 6.5, 6.5}
 
        Dim nud_precision As Integer = 200 'Steps im Achsenbereich
 
        With chart1
            .Series.Clear()
            .Series.Add("Demo1")
            .Series.Add("Demo2")
            .Series.Add("Demo3")
 
            .ChartAreas.Clear()
            .ChartAreas.Add("Area1")
 
            With chart1.ChartAreas(0).AxisY
                'Achsenbereich ....
                .Minimum = 70
                .Maximum = 180
                .Interval = 20
                'ins Numeric-Control übertragen
                nud.Minimum = CDec(.Minimum)
                nud.Maximum = CDec(.Maximum)
                Dim pr As Double = (.Maximum - .Minimum) / nud_precision
                nud.Increment = CDec(pr)
                nud.DecimalPlaces = 0
                If pr < 10 Then nud.DecimalPlaces = 1
                If pr < 1 Then nud.DecimalPlaces = 2
                If pr < 0.1 Then nud.DecimalPlaces = 3
            End With
 
            With .Series("Demo1")
                For i As Integer = 0 To x.Length - 1
                    .Points.AddXY(x(i), y(i))
                    .Points(i).Color = Color.Green
                Next i
                .ChartType = SeriesChartType.Point
            End With
 
            With .Series("Demo2")
                For i As Integer = 0 To x.Length - 1
                    .Points.AddXY(x2(i), y2(i))
                    .Points(i).Color = Color.Black
                Next i
                .ChartType = SeriesChartType.Point
            End With
 
        End With
    End Sub
 
 
    Dim MouseDataPoint As DataPoint
    Dim SetDataPoint As DataPoint
 
 
    Private Sub Chart1_MouseDown(sender As Object, _
                     e As MouseEventArgs) Handles chart1.MouseDown
 
        Dim htr As HitTestResult = chart1.HitTest(e.X, e.Y)
 
        MouseDataPoint = Nothing
        SetDataPoint = Nothing
 
        If htr.ChartElementType = ChartElementType.DataPoint Then
            MouseDataPoint = _
               chart1.Series(htr.Series.Name).Points(htr.PointIndex)
 
            With MouseDataPoint
                .MarkerStyle = MarkerStyle.Cross
                .MarkerColor = Color.Red
                .MarkerSize = 12
                .Tag = htr.PointIndex
            End With
 
            SetDataPoint = MouseDataPoint
        End If
    End Sub
 
 
    Private Sub chart1_MouseMove(sender As Object, _
            e As System.Windows.Forms.MouseEventArgs) _
            Handles chart1.MouseMove
 
        If e.Y < 0 Or e.Y >= chart1.Height Then Exit Sub
 
        If MouseDataPoint Is Nothing Then Exit Sub
 
        With chart1.ChartAreas(0)
            Dim yval As Double = .AxisY.PixelPositionToValue(e.Y)
 
            If yval >= .AxisY.Minimum And yval <= .AxisY.Maximum Then
                MouseDataPoint.YValues(0) = yval
                nud.Value = CDec(SetDataPoint.YValues(0))
            End If
        End With
    End Sub
 
 
    Private Sub chart1_MouseUp(sender As Object,
        e As System.Windows.Forms.MouseEventArgs) Handles chart1.MouseUp
 
        If MouseDataPoint Is Nothing Then Exit Sub
 
        With MouseDataPoint
            .MarkerStyle = MarkerStyle.None
            .MarkerSize = 5
            .MarkerColor = MouseDataPoint.Color
        End With
 
        chart1.Invalidate()
 
        nud.Value = CDec(SetDataPoint.YValues(0))
        MouseDataPoint = Nothing
    End Sub
 
 
    Private Sub nud_ValueChanged(sender As Object, _
        e As System.EventArgs) Handles nud.ValueChanged
 
        If SetDataPoint Is Nothing Then Exit Sub
        SetDataPoint.YValues(0) = nud.Value
        chart1.Invalidate()
 
    End Sub
End Class