Private pDrawingPoints As New List(Of Point)
   Private pLastPoint As Point
   Private pAllowDraw As Boolean
   Private pLineColor As Color = Color.Red
   Private pLineWidth As Integer = 2
 
   Private Sub PictureBox1_MouseDown(ByVal sender As System.Object, ByVal e As _
     System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseDown
      If e.Button = Windows.Forms.MouseButtons.Left Then
         pAllowDraw = True
         pLastPoint = e.Location
         pDrawingPoints.Clear()
         pDrawingPoints.Add(e.Location)
      End If
   End Sub
 
   Private Sub PictureBox1_MouseMove(ByVal sender As System.Object, ByVal e As _
     System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseMove
      If pAllowDraw AndAlso e.Location <> pLastPoint Then
         Using g As Graphics = PictureBox1.CreateGraphics
            g.FillEllipse(New SolidBrush(pLineColor), pLastPoint.X - pLineWidth _
              \ 2, pLastPoint.Y - pLineWidth \ 2, pLineWidth, pLineWidth)
            g.DrawLine(New Pen(pLineColor, pLineWidth), pLastPoint, e.Location)
            pLastPoint = e.Location
            pDrawingPoints.Add(e.Location)
         End Using
      End If
   End Sub
 
   Private Sub PictureBox1_MouseUp(ByVal sender As System.Object, ByVal e As _
     System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseUp
      pAllowDraw = False
 
      Using g As Graphics = PictureBox1.CreateGraphics
         g.Clear(Color.White)
         g.SmoothingMode = Drawing2D.SmoothingMode.AntiAlias
         g.DrawLines(New Pen(pLineColor, pLineWidth), pDrawingPoints.ToArray)
      End Using
   End Sub