Analysis of Data of one Hour and put it in graph

Question

 I am Getting One image Per second.means more than 3000 image in hour . i have to show it in a chart. i use a chart componet of vb.net. In the listbox one all sizes of the image are available .  The loop is not working properly ?
 Dim s As New Series
        Chart1.Series.Clear()
        Chart1.Titles.Add("Demo")
        s.ChartType = SeriesChartType.Line
        Dim lMinutes As Long
        Dim lSeconds As Long
        lSeconds = ListBox1.Items.Count
        lMinutes = (Int(lSeconds / 60))
        '' lSeconds = Int(lSeconds Mod 60)
        MessageBox.Show(lMinutes)
        For t As Integer = 1 To lMinutes
            For y As Integer = 0 To ListBox1.Items.Count - 1
                s.Points.AddXY(t, Val(ListBox1.Items.Item(y).ToString))
            Next
        Next
        Chart1.Series.Add(s)
Satyajit Rath

Answer 1

Hi,
first, switch Option Strict On an fix the compile errors.
lMinutes and lSeconds don't need to be declared As Long because ListBox1.Items.Count returns an Integer.
With new VB.Net projects, it's not required to use the VB6 emulation layer. The Val() function is part of it. Use Integer.Parse instead.
You must make the inner loop depend on the outer loop. There are several ways to write the loop(s). It depends on how you want the chart to be displayed. I'm not sure about that. Your code makes me assume, you want to display the values within one minute
at the same X location of the chart. However, then the ChartType "Line" doesn't seem to be appropriate. Let me know if this is correct. I've changed it to "Point" for testing. Then you can write it like this:
For t As Integer = 1 To lMinutes
For y As Integer = (t - 1) * 60 To Math.Min(t * 60 - 1, ListBox1.Items.Count - 1)
s.Points.AddXY(t, Integer.Parse(ListBox1.Items.Item(y).ToString))
Next
Next
Before, you have to change one line:
lMinutes = CInt(Math.Ceiling(lSeconds / 60))
Armin