Public Class Form1
    Private Sub ZoomingPictureBox1_MouseWheel(sender As Object, e As _
      System.Windows.Forms.MouseEventArgs) Handles ZoomingPictureBox1.MouseWheel
        ' Hier gehts
        Debug.Print(e.Delta)
    End Sub
End Class

Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Drawing.Drawing2D
 
Public Class ZoomingPictureBox
    Friend oBitmap As Bitmap
    Friend tBitmap As Bitmap
    Friend tBitmap_width As Single = 0
    Friend tBitmap_height As Single = 0
    Friend tBitmap_zoom As Single = 1
 
    Public Sub New()
 
        ' This call is required by the designer.
        InitializeComponent()
 
 
        ' Add any initialization after the InitializeComponent() call.
        oBitmap = Image.FromFile("demopic.jpg")
        show_PicSector()
    End Sub
 
    Friend Sub show_PicSector()
        If tBitmap Is Nothing Then
            tBitmap = New Bitmap(PB.Width, PB.Height, _
              Imaging.PixelFormat.Format24bppRgb)
            tBitmap_width = tBitmap.Width
            tBitmap_height = tBitmap.Height
        Else
            If tBitmap.Width = tBitmap_width Or tBitmap.Height = tBitmap_height _
              Then
                tBitmap.Dispose()
                tBitmap = New Bitmap(PB.Width, PB.Height, _
                  Imaging.PixelFormat.Format24bppRgb)
            End If
        End If
        Dim bmGraphics As Graphics = Graphics.FromImage(tBitmap)
        bmGraphics.InterpolationMode = InterpolationMode.HighQualityBicubic
 
        bmGraphics.DrawImage(oBitmap, New Rectangle(0, 0, PB.Width, PB.Height), _
          New Rectangle(0, 0, oBitmap.Width / tBitmap_zoom, oBitmap.Height / _
          tBitmap_zoom), GraphicsUnit.Pixel)
        bmGraphics.Dispose()
        PB.Image = tBitmap
        PB.Refresh()
    End Sub
 
    Private Sub PB_MouseWheel(sender As Object, e As _
      System.Windows.Forms.MouseEventArgs) Handles PB.MouseWheel
        ' Das geht nicht! Es kommt nie zu einem Event.
        ' Auch das UserControll (ZoomingPictureBox) selbst kommt kein Event       
        Debug.Print(e.Delta)
        PB.Refresh()
    End Sub
End Class

befficient - consulting & programming
Tracability Know-How seit über 5 Jahren
itac (MES.Suite) Client Programmierung