string manipulation question

[nm_114]

when is it ok to do pch++ and when should you use CharNext/_tcsinc? I'm guessing pch++ is fine for ansi char* and unicode TCHAR* for english, so do you use CharNext/_tcsinc for programs that will have text in a non-english encoding, a non-western european encoding? - thanks

[Jose Lamas Rios]

pch++ can be used for WCHAR* or, if you know the string is using a code page in which there are no multi-byte chars (e.g., English, Spanish, French), for char* too. CharNext or _tcsinc are used when you want to write code that can be used, whithout changes, either for SBCS, MBCS, or Unicode builds. For example, the following code:

_TCHAR buffer[] = _T("This is a test");
int nLen = 0;
for (const _TCHAR* pch = buffer; *pch; pch = _tcsinc(pch))
{
  nLen++;
}

gets expanded as follows:

// SBCS (when neither _MBCS nor _UNICODE are defined)
char buffer[] = "This is a test";
int nLen = 0;
for (const char* pch = buffer; *pch; pch = _strinc(pch))
{
  nLen++;
}

// UNICODE (when _UNICODE is defined)
wchar_t buffer[] = L"This is a test";
int nLen = 0;
for (const wchar_t* pch = buffer; *pch; pch = _wcsinc(pch))
{
  nLen++;
}

// MBCS (when _MBCS is defined)
char buffer[] = "This is a test";
int nLen = 0;
for (const char* pch = buffer; *pch; pch = _mbsinc(pch))
{
  nLen++;
}

See also: A Sample Generic-Text Program[^] -- jlr http://jlamas.blogspot.com/[^]

[nm_114]

thanks for the reply. just wondering, do you know of any reference that tells which code pages are multi-byte, which are single-byte? - thanks