Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal _
  e As System.EventArgs) _
    Handles ComboBox1.SelectedIndexChanged
        Call TextBoxRemove()
        Select Case ComboBox1.SelectedItem
            Case "Rund" : DmZyl = New TextBox
                DmZyl.Bounds = New Rectangle(New Point(209, 154), New Size(87, _
                  20))
                DmZyl.Text = "Ø?"
                Controls.Add(DmZyl)
                HZyl = New TextBox
                HZyl.Bounds = New Rectangle(New Point(209, 188), New Size(87, _
                  20))
                HZyl.Text = "Länge?"
                Controls.Add(HZyl)
            Case "Rohr" : ADmRoh = New TextBox
                ADmRoh.Bounds = New Rectangle(New Point(209, 154), New Size(87, _
                  20))
                ADmRoh.Text = "Außen-Ø?"
                Controls.Add(ADmRoh)
                WdRoh = New TextBox
                WdRoh.Bounds = New Rectangle(New Point(350, 154), New Size(87, _
                  20))
                WdRoh.Text = "Wandstärke?"
                Controls.Add(WdRoh)
                HRoh = New TextBox
                HRoh.Bounds = New Rectangle(New Point(209, 188), New Size(87, _
                  20))
                HRoh.Text = "Länge?"
                Controls.Add(HRoh)
            Case "Rechteck" : AQuad = New TextBox
                AQuad.Bounds = New Rectangle(New Point(209, 154), New Size(87, _
                  20))
                AQuad.Text = "a?"
                Controls.Add(AQuad)
                BQuad = New TextBox
                BQuad.Bounds = New Rectangle(New Point(350, 154), New Size(87, _
                  20))
                BQuad.Text = "b?"
                Controls.Add(BQuad)
                HQuad = New TextBox
                HQuad.Bounds = New Rectangle(New Point(209, 188), New Size(87, _
                  20))
                HQuad.Text = "Länge?"
                Controls.Add(HQuad)
            Case "Sechseck" : SWSechsE = New TextBox
                SWSechsE.Bounds = New Rectangle(New Point(209, 154), New Size( _
                  87, 20))
                SWSechsE.Text = "SW?"
                Controls.Add(SWSechsE)
                HSechsE = New TextBox
                HSechsE.Bounds = New Rectangle(New Point(209, 188), New Size( _
                  87, 20))
                HSechsE.Text = "Länge?"
                Controls.Add(HSechsE)
            Case Else
                MessageBox.Show("Fehler")
        End Select
    End Sub

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