Option Explicit

Private Sub Form_Load()
  With picQuelle
    .Visible = False
    .AutoSize = True
    .AutoRedraw = True
  End With

  With picZiel
    .AutoRedraw = True
  End With

  On Error Resume Next
  picQuelle.Picture = LoadPicture(App.Path & "\" & "VBfun.gif")
  ResizeGraficToPicBox picQuelle, picZiel
End Sub

Private Sub ResizeGraficToPicBox(ByVal vpicQuelle As PictureBox, _
                              ByVal vpicZiel As PictureBox)
  Dim sngRatio As Single
  Dim sngWidth As Single
  Dim sngHeight As Single
  Dim sngPosX As Single
  Dim sngPosY As Single

  vpicZiel.Cls

  If optGroesse(0) Then
    sngWidth = vpicQuelle.ScaleWidth
    sngHeight = vpicQuelle.ScaleHeight

    If vpicQuelle.ScaleWidth > vpicZiel.ScaleWidth Or _
          vpicQuelle.ScaleHeight > vpicZiel.ScaleHeight Then
      sngPosX = 0
      sngPosY = 0
    Else
      sngPosX = (vpicZiel.ScaleWidth - sngWidth) / 2
      sngPosY = (vpicZiel.ScaleHeight - sngHeight) / 2
    End If

  Else
    sngRatio = vpicQuelle.ScaleWidth / vpicQuelle.ScaleHeight

    sngWidth = vpicZiel.ScaleWidth
    sngHeight = vpicZiel.ScaleHeight

    If (sngWidth / sngHeight) > sngRatio Then
      sngWidth = sngRatio * sngHeight
    Else
      sngHeight = sngWidth / sngRatio
    End If

    sngPosX = (vpicZiel.ScaleWidth - sngWidth) / 2
    sngPosY = (vpicZiel.ScaleHeight - sngHeight) / 2
  End If

  vpicZiel.PaintPicture vpicQuelle.Picture, _
        sngPosX, sngPosY, sngWidth, sngHeight
End Sub

Private Sub optGroesse_Click(Index As Integer)
  ResizeGraficToPicBox picQuelle, picZiel
End Sub

Private Sub cmdGrafikLaden_Click()
  Dim strFilter As String

  CommonDialog1.CancelError = True

  On Error GoTo ErrHandler

  strFilter = "Alle Grafiken (*.gif;*.jpg;*.ico;*.bmp;*.wmf)" & _
                            "|*.gif;*.jpg;*.ico;*.bmp;*.wmf|"
  strFilter = strFilter & "GIF Files (*.gif)|*.gif|"
  strFilter = strFilter & "JPEG Files (*.jpg)|*.jpg|"
  strFilter = strFilter & "Icon Files (*.ico)|*.ico|"
  strFilter = strFilter & "Windows Bitmap (*.bmp)|*.bmp|"
  strFilter = strFilter & "Windows Meta File (*.wmf)|.wmf"

  With CommonDialog1
    .Filter = strFilter
    .DialogTitle = "Grafik laden"
    .ShowOpen

    If Len(.FileName) <> 0 Then
      picQuelle.Picture = LoadPicture(.FileName)
      ResizeGraficToPicBox picQuelle, picZiel
    End If
  End With

  On Error GoTo 0

  Exit Sub
ErrHandler:
End Sub