Dim text As String = _
      "Ich; chb; hbr; bra: rau; auc; uch; che; heh; ehi; hil; ilf; lfe"
 
   'Aufspalten am Strichpunkt
   Dim parts() As String = text.Split(";"c)
 
   Dim freq As New Dictionary(Of String, Integer)
 
   For i As Integer = 0 To parts.Length - 1
       parts(i) = parts(i).Trim 'Leerzeichen Anfang/Ende entfernen
       If freq.ContainsKey(parts(i)) Then
          'Element bereits vorhanden: zählen
          freq(parts(i)) += 1
       Else
          'Element hinzufügen
          freq.Add(parts(i), 1)
       End If
   Next i