VB6 - Huge (>2GB) File I/O Class

[Jonney]

Since this Class does not deal with text at all, there is no need for the W entrypoints.

However if you want to use Unicode file names then you have a valid point, and CreateFile needs to be CreateFileW with a few other minor changes to its signature and call.

Use CreateFileW in your OpenFile function.

I have no idea why you are using LCMapString though, except perhaps as a fancy version of StrConv?

I just copy all APIs from my another project which deal with Unicode text file. LCMAPStringW for GB2GBK conversion.

Public Function GB2GBK(ByVal CSstring As String) As String

  Dim lLen As Long
  Dim CTString As String

    On Error GoTo ToExit

    If CSstring = vbNullString Then Exit Function
    If m_bisNT Then
        lLen = lstrlenW(StrPtr(CSstring))
        CTString = Space$(lLen)
        LCMapStringW &H804, &H4000000, StrPtr(CSstring), lLen, StrPtr(CTString), lLen * 2
        GB2GBK = CTString
      Else
        lLen = lstrlen(CSstring)
        CTString = Space$(lLen)
        LCMapString &H804, &H4000000, CSstring, lLen, CTString, lLen
        GB2GBK = CTString
    End If

Exit Function

ToExit:
    GB2GBK = vbNullString

End Function

The nice thing about having the source is that you can hack away and make any customization you want though. If there really is a bug perhaps you can explain it in more detail?

Public Function ReadBytes(ByRef Buffer() As Byte) As Long

RaiseErrorIfClosed

If ReadFile(hFile, _
Buffer(LBound(Buffer)), _
UBound(Buffer) - LBound(Buffer) + 1, _
ReadBytes, _
0) Then

If ReadBytes = 0 Then
fEOF = True
ElseIf ReadBytes < UBound(Buffer) - LBound(Buffer) + 1 Then
ReDim Preserve Buffer(ReadBytes - 1)
End If
Else
RaiseError HBF_READ_FAILURE
End If
End Function