Private _Left As Integer
 
    Private Sub Label1_MouseDown(ByVal sender As System.Object, ByVal e As _
      System.Windows.Forms.MouseEventArgs) Handles Label1.MouseDown
        _Left = Label1.Location.X + 1
        Sekrechte_Linie_ziehen(_Left)
    End Sub
 
    Private Sub Sekrechte_Linie_ziehen(ByVal Left As Long)
        Dim g As Graphics
        Dim p As Pen
 
        g = Me.CreateGraphics()
 
        'LinienFarbe, LinienStärke
        p = New Pen(System.Drawing.Color.Red, 1)
 
        'Linie => (pen=Farbe, Linienstärke), x1, y1, x2, y2
        'Senkrechte Linien  (Pen,  LEFT (von unten), Linienlänge, Left(von 
        ' oben), TOP )
        g.DrawLine(p, Left, 870, Left, 37)
    End Sub
 
    Private Sub Label1_MouseLeave(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Label1.MouseLeave
        Me.Invalidate(New Rectangle(_Left, 37, 1, 870))
    End Sub

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