Option Compare Database
Option Explicit
Const Win =  1 , Dos =  2 , Koi =  3 , Iso =  5 

Public Function Recode(Char As String, Src, Dest) As String
Const wDos As String = "°±Ііґµ¶·ё№є»јЅѕїАБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧрЩЪЫЬЭЮЯтуфхцчшщсыьэюяШъЂЃ‚ѓ„…†‡€‰Љ‹ЊЌЋЏђ‘’“”•–—˜™љ›њќћџ ЎўЈ¤Ґ¦§Ё©Є«¬­®Їабвгдежзийклмноп"
Const wIso As String = "°±Ііґµ¶·ё№є»јЅѕїАБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧўЩЪЫЬЭЮЯтуфхцчшщсыьэюяШъ°±Ііґµ¶·ё№є»јЅѕїАБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯабвгдежзийклмноп"
Const wKoi As String = "ђ‘’Ѓ‡Іґ§¦µЎЁ®­¬ѓ„‰€†ЂЉЇ°«Ґ»ё± ѕ№є¶·Є©ў¤Ѕі…‚ЌЊЋЏ‹™˜“›џ—њћЈ–љќ”їј•бвчздецъйклмнопртуфхжигюыэящшьасБВЧЗДЕЦЪЙКЛМНОПРТУФХЖИГЮЫЭЯЩШЬАС"
Const wWin As String = "ЂЃ‚ѓ„…†‡€‰Љ‹ЊЌЋЏђ‘’“”•–—˜™љ›њќћџ ЎўЈ¤Ґ¦§Ё©Є«¬­®Ї°±Ііґµ¶·ё№є»јЅѕїАБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯабвгдежзийклмнопрстуфхцчшщъыьэюя"
Const NotRecodedChar As String = "?"

If Src = Dest Then
Recode = Char
Exit Function
End If

Dim t As String, i As Long, tt As String, a As Long, ss As String, ch As String
If Src = Win Then
t = Char
Else
Select Case Src
Case Koi: ss = wKoi
Case Dos: ss = wDos
Case Iso: ss = wIso
End Select
For i =  1  To Len(Char)
ch = Mid(Char, i,  1 )
If Asc(ch) <  128  Then
t = t & ch
Else
a = InStr( 1 , ss, ch, vbBinaryCompare)
If a =  0  Then
t = t & NotRecodedChar
Else
t = t & Mid$(wWin, a,  1 )
End If
End If
Next i
End If

If Dest = Win Then
Recode = t
Else
Select Case Dest
Case Koi: ss = wKoi
Case Dos: ss = wDos
Case Iso: ss = wIso
End Select
For i =  1  To Len(Char)
ch = Mid(t, i,  1 )
If Asc(ch) <  128  Then
tt = tt & ch
Else
a = InStr( 1 , wWin, ch, vbBinaryCompare)
If a =  0  Then
tt = tt & NotRecodedChar
Else
tt = tt & Mid$(ss, a,  1 )
End If
End If
Next i
Recode = tt
End If
End Function