Private Sub ändereSelectedSchriftschnitt(sSchnitt As Integer)
 
        Dim rtb = tsc_TextEditor_RTFBox
 
        ' Selektion merken
        Dim rtbs = rtb.SelectionStart
        Dim rtbsl = rtb.SelectionLength
 
        If rtb.SelectionLength > 0 Then
 
            Dim rt = rtb.SelectedRtf
 
            ' Bold Start und Ende entfernen
            If (sSchnitt And 1) = 1 Or (sSchnitt And 1) = 0 Then
                For Each m As Match In Regex.Matches(rt, "\\b0", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\b\s", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\b", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length) 
                Next
            End If
 
            ' Italic Start und Ende entfernen
            If (sSchnitt And 2) = 2 Or (sSchnitt And 1) = 0 Then
                For Each m As Match In Regex.Matches(rt, "\\i0", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\i\s", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\i", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length) 
                Next
            End If
 
            ' Underline Start und Ende entfernen
            If (sSchnitt And 4) = 4 Or (sSchnitt And 1) = 0 Then
                For Each m As Match In Regex.Matches(rt, "\\ulnone", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\ul\s", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\ul", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
            End If
 
            ' Strikeout Start und Ende entfernen
            If (sSchnitt And 8) = 8 Or (sSchnitt And 1) = 0 Then
                For Each m As Match In Regex.Matches(rt, "\\strike0", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\strike\s", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length)
                Next
                For Each m As Match In Regex.Matches(rt, "\\strike", _
                  RegexOptions.RightToLeft)
                    rt = rt.Remove(m.Index, m.Length) 
                Next
            End If
 
            ' Schriftschnitt am Anfang und Ende der Selektion setzen
            Dim n As Match
            n = Regex.Match(rt, "\\pard")
 
            ' Bold
            If (sSchnitt And 1) = 1 Then
                rt = rt.Insert(n.Index, $"\b") & rt & "\b0"
            End If
 
            ' Italic
            If (sSchnitt And 2) = 2 Then
                rt = rt.Insert(n.Index, $"\i") & rt & "\i0"
            End If
 
            ' Underline
            If (sSchnitt And 4) = 4 Then
                rt = rt.Insert(n.Index, $"\ul") & rt & "\ulnone"
            End If
 
            ' StrikeOut
            If (sSchnitt And 8) = 8 Then
                rt = rt.Insert(n.Index, $"\strike") & rt & "\strike0"
            End If
 
            ' In RTF übernehmen
            rtb.SelectedRtf = rt
 
            ' Selektion erneuern
            rtb.SelectionStart = rtbs
            rtb.SelectionLength = rtbsl
        End If
    End Sub