Drawing/Plotting in VB.NET

[alain44]

Hi
Can someone help me plotting results on a picturebox using VB.NET ?
Based on VB’s help I made up the following code – which works fine as long as the Do-While-loop is disconnected by the ‘Exit Sub’ in line 6 of sub Button1_Click – but if the loop is active as needed for plotting there happens no drawing at all.
What’s wrong ???

Public Class AnalResult
    Dim RcDraw As Rectangle
    Dim PenWidth As Integer = 4
    Dim Warten As Boolean
    Dim Pen1 As New Pen(Color.Blue, PenWidth)
    'Dim e1 As New System.Windows.Forms.PaintEventArgs
    Public PosTrade%, NegTrade%, PosTradeT#, NegTradeT#, PosTop#, NegBottom#, BiggestLoss#, LongestDown%, Massst#, NullN#
 
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Static i% = 0
        Do While i < 2000
            i = i + 4
            Z(i)
            'Exit Sub ‘ <<<<<<<<< if no exit – no drawing at all
        Loop
    End Sub
 
    Public Sub Z(ByVal Yw%)
        If RcDraw.X = 0 Then RcDraw.X = 20
        Dim i%
        i = PictureBox1.Height - (G_ResT * Massst + NullN)
        If Yw = 0 Then Yw = i
        RcDraw.X = RcDraw.X + 4
        If PictureBox1.Width < RcDraw.X + 8 Then
            Exit Sub
            PictureBox1.Width = RcDraw.X + 8
            Me.Width = PictureBox1.Width + (1137 - 744)
        End If
        RcDraw.Width = 4 ' RcDraw.X - e.X
        RcDraw.Height = 4 ' RcDraw.Y - e.Y
        RcDraw.Y = Yw ' 81 ' e.Y
        PictureBox1.Invalidate(RcDraw)
    End Sub
 
    Private Sub PictureBox1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles PictureBox1.Paint
        e.Graphics.DrawRectangle(Pens.Blue, RcDraw)
        'e.Graphics.DrawRectangle(New Pen(Color.Blue, PenWidth), RcDraw)
    End Sub
End Class
 

Many thanks for help !!
Alain

[debasisdas]

Question moved to .NET Forum.