Public Class Form1
   Dim pPoints As New List(Of Point)
 
   Private Sub PictureBox1_MouseDown(ByVal sender As System.Object, ByVal e As _
     System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseDown
      pPoints.Clear()
   End Sub
 
   Private Sub PictureBox1_MouseMove(ByVal sender As System.Object, ByVal e As _
     System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseMove
      If e.Button = Windows.Forms.MouseButtons.Left Then
         pPoints.Add(e.Location)
      End If
   End Sub
 
   Private Sub PictureBox1_MouseUp(ByVal sender As System.Object, ByVal e As _
     System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseUp
      Dim g As Graphics = PictureBox1.CreateGraphics
 
      g.SmoothingMode = Drawing2D.SmoothingMode.AntiAlias
      g.DrawLines(Pens.Black, pPoints.ToArray)
 
      g.Dispose()
   End Sub
End Class