Преобразование символом в символы другой раскладки

if a="b" then
a="и"
end if

Select PEREMEN
Case b
PEREMEN = "и"
Case j
PEREMEN = "о"
Case v
PEREMEN = "m"
' и т.д. и т.п.
End Select

Dim direction As Boolean
'Если его значение -- True, тогда перевод из русского в транслит, и наоборот
Private Function Translate(ByVal strFullString As String, ByVal direction As Boolean) As String
Dim i As Integer
Dim bRussian(35) As String
Dim bTrans(35) As String
Dim lTrans() As String = {"j", "c", "u", "k", "e", "n", "g", "sh", "sh", "z", "h", "'", "f", "y", "v", "a", "p", "r", "o", "l", "d", "zh", "e", "ja", "ch", "s", "m", "i", "t", "'", "b", "ju", "йа", "йу", "зх", "цх"}
Dim lRussian() As String = {"й", "ц", "у", "к", "е", "н", "г", "ш", "щ", "з", "х", "ь", "ф", "ы", "в", "а", "п", "р", "о", "л", "д", "ж", "э", "я", "ч", "с", "м", "и", "т", "ь", "б", "ю", "я", "ю", "ж", "ч"}
If direction = True Then
      For i = 0 To 35
           bRussian.SetValue(lRussian(i).ToUpper.ToString, i)
           bTrans.SetValue(lTrans(i).ToUpper.ToString, i)
           strFullString = strFullString.Replace(lRussian(i).ToString, lTrans(i).ToString)
           strFullString = strFullString.Replace(bRussian(i).ToString, bTrans(i).ToString)
      Next
    Else
      For i = 0 To 35
        bRussian.SetValue(lRussian(i).ToUpper.ToString, i)
        bTrans.SetValue(lTrans(i).ToUpper.ToString, i)
        strFullString = strFullString.Replace(lTrans(i).ToString, lRussian(i).ToString)
        strFullString = strFullString.Replace(bTrans(i).ToString, bRussian(i).ToString)
      Next
    End If
    Return strFullString
End Function

    Private Function createDict() As Dictionary(Of Char, Char)
        Dim chDi As New Dictionary(Of Char, Char)
        Dim ru() As Char = {"Ф", "И", "С", "В", "У", "А", "П", "Р", "Ш", "О", "Л", "Д", "Ь", "Т", "Щ", "З", "Й", "К", "Ы", "Е", "Г", "М", "Ц", "Ч", "Н", "Я"}
        For i = 65 To 90
            chDi.Add(ChrW(i), ru(i - 65))
        Next
        For i = 97 To 122
            chDi.Add(ChrW(i), Char.ToLower(ru(i - 97)))
        Next
        Return chDi
    End Function
    Public Function findKey(ByVal sm As Char, ByVal di As Dictionary(Of Char, Char)) As Char
        Dim ch As Char = ""
        If Char.IsLetter(sm) Then
            If AscW(sm) < 1000 Then
                If di.ContainsKey(sm) Then
                    ch = di.Item(sm)
                End If
            Else
                If di.ContainsValue(sm) Then
                    Dim fch = From d In di Where d.Value = sm
                    ch = fch(0).Key
                End If
            End If
        End If
        Return ch
    End Function
    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        Dim ddi As Dictionary(Of Char, Char) = createDict()
        Dim ss As Char = InputBox("Ввод")
        Dim s As Char = findKey(ss, ddi)
        MsgBox(s)
    End Sub