Public Class Line
    Dim Basepoints As List(Of Basepoint)
    Dim count As Integer = 0                        'Anzahl der Punkte der Linie
 
    Sub addPoint(ByVal e As MouseEventArgs)         'neuen Punkt hinzufügen
        Dim after As Point
        Dim before As Point
        '...Tangenten berechnen...
        Basepoints.Add(New Basepoint)
        Basepoints(count).Add(e, after, before)
        count = count + 1
    End Sub
 
    Sub Check(ByVal e As MouseEventArgs)
        'Überprüfen, ob die Maus über einem Kontrollpunkt ist
    End Sub
 
End Class

Public Class Basepoint
    Dim Main_Point As Point
    Dim Tang_after As Point
    Dim Tang_before As Point
    Dim Line_type As LType
    Dim Point_Type As PType
    Dim Kurve As List(Of Point)
 
    Sub Add(ByVal e As MouseEventArgs, ByVal T_after As Point, ByVal T_before _
      As Point)
        Main_Point = e.Location
        Tang_after = T_after
        Tang_before = T_before
        '...usw für die anderen Eigenschaften
    End Sub
 
    Sub Calculate()
        'Spline berechnen
    End Sub
 
    Enum PType
        corner
        tangential
        symetric
    End Enum
 
    Enum LType
        Empty
        Line
        Spline
    End Enum
End Class

Public Class Form1
 
    Dim Lines As New Line
 
    Private Sub PictureBox1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles PictureBox1.Click
        Lines.addPoint(e)
    End Sub
 
End Class