Chart Control - real time data - scrolling

Question

Hi

Having problems with chart control with real time data adding two points and getting it to automatically scroll as data is added

Tried all the samples and spent hours googling but nothing I try works - closest I got was with sample in https://code.msdn.microsoft.com/Samples-Environments-for-b01e9c61/view/SamplePack but this didn't work for two points in line chart

So I have following code currently

All works and graph shows, but as more data is added it is slowly compressed and cannot be legible - so need to scroll automatically as data is added so always seeing new values but can move scroll bar back to see old

Please advise

Thanks

 Dim graph_upload As New DataVisualization.Charting.Series
    Dim graph_download As New DataVisualization.Charting.Series

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

' configure graph
        graph_upload.Name = "Upload"
        graph_upload.ChartType = DataVisualization.Charting.SeriesChartType.Line
        graph_upload.Color = Color.Red
        graph_upload.BorderWidth = 2
        graph_upload.ToolTip = "#VAL{0.00}Kb"
        Chart1.Series.Add(graph_upload)
        graph_download.Name = "Download"
        graph_download.ChartType = DataVisualization.Charting.SeriesChartType.Line
        graph_download.Color = Color.Blue
        graph_download.BorderWidth = 2
        graph_download.ToolTip = "#VAL{0.00}Kb"
        Chart1.Series.Add(graph_download)

        Chart1.ChartAreas("ChartArea1").AxisX.Title = "Time (seconds)"
        Chart1.ChartAreas("ChartArea1").AxisY.Title = "Kb/sec"

End Sub


And then I am adding points in a timer - the up/down values contain current upload/download speeds

graph_upload.Points.Add(Up / 1024)
        graph_download.Points.Add(Down / 1024)

---

Darren Rose

Answer 1

Please check the below post, I think it answers your question:

Real time data to chart control

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Fouad Roumieh

Answer 2

Thanks - think I have now got it only showing latest points but can't seem to get scroll bar to work - as when it appears the data then keeps going but scrollbar stays left rather than right

---

Darren Rose

Answer 3

Each time you adding points try to reset the view and scroll to the max in xAxis, something like:

Chart1.ChartAreas(0).AxisX.ScaleView.Zoom(0, xmax)
Chart1.ChartAreas(0).AxisX.ScaleView.Position = xmax

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Fouad Roumieh

Answer 4

Thanks, tried that but then it seems to scroll too quickly and I can't see data as it is further to the left off the current view

Never realised working with charts could be such a pain

Also tried getting it to recalculate y axis so scale correct to what is shown but that doesn't work unless I remove points as I add them - and then bottom axis doesn't increment like it does without

Think I will give up on this for now

Thanks for helping

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Darren Rose