Public Class Form1
' Dim bmp As New System.Drawing.Bitmap("Dateipfad+Name")   ' läd ein Bild in _
  eine Bitmap
    Dim bmp As New Bitmap(300, 300)                 ' legt eine neue Bitmap an
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        For i As Int32 = 1 To 300 Step 5
            bmp.SetPixel(i, i, Color.Black)
        Next
        PictureBox1.Image = bmp
    End Sub
End Class