Dim gp As New GraphicsPath()
    Private LastMousePos As Point
 
    Protected Overrides Sub OnPaint(ByVal e As _
      System.Windows.Forms.PaintEventArgs)
        e.Graphics.SmoothingMode = SmoothingMode.HighQuality
 
        Dim P As New Pen(Color.Black, 5)
        e.Graphics.DrawPath(P, gp)
        P.Dispose()
    End Sub
 
    Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseMove
        If e.Button = MouseButtons.Left Then
            gp.AddLine(LastMousePos, New Point(e.X, e.Y))
            Invalidate()
        End If
        LastMousePos = New Point(e.X, e.Y)
    End Sub