Re: Switching from Multi-Byte to Unicode character sets

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"jc" <jc@xxxxxxxxxxxxxxxxxxxxxxxxx> ha scritto nel messaggio
news:08230DC5-0A9E-468F-AE81-0054ED8ED0B4@xxxxxxxxxxxxxxxx
Hello,
This compiles OK using Multi-Byte character set,
but when I switch to Unicode I get an error.
char reply[256] = _T("olleh");

Because when you switch to Unicode, _T("...") macro expands to L"...", so
your code becomes:

char reply[ 256 ] = L"olleh"

which is wrong (because the L"olleh" is a wchar_t string, not a char
string).


I know this will fix the error with the Unicode compile,
wchar_t reply[256] = _T("olleh");
but this causes many other conversion problems in the program.

The correct code should be:

TCHAR reply[ 256 ] = _T("olleh");

TCHAR will expands to wchar_t in Unicode builds, and to char in ANSI/MBCS
builds.

BTW: why don't you use CString instead of raw TCHAR arrays?


Is there some other conversion macro that I could use instead of _T(),
instead of having to change from char to a wchar_t?

If you want to convert from generic TCHAR to char, you may want to use ATL
helper classes, like CT2A:

CT2A reply( _T("olleh") );

Both in Unicode and in ANSI/MBCS builds, your 'reply' variable is a RAII
buffer made by char's.

More information here:

http://msdn.microsoft.com/en-us/library/87zae4a3.aspx

HTH,
Giovanni


.

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