Re: How to write vector<CString> to a text file?
"DavidTM" <DavidTM@discussions.microsoft.com> ha scritto nel messaggio
news:72D50D62-691F-4ED8-8209-44D93F9A5AE3@microsoft.com...
I read a text file into vector<CString>, manipulated it and now need to
write
the vector back to a text file. I was doing this with ofstream:
std::vector<CString> fileContents;
std::ofstream opFile(opFileName.c_str(), std::ios::out);
for (size_t n=0; n<fileContents.size(); ++n)
{
opFile << fileContents[n] << std::endl;
}
but I am now using Unicode strings so that method won't work.
[...]
I would like the output file to be ASCII, not UTF-16. How can I specify
that?
My understanding of your problem is that you are using CString, you are
doing a Unicode build (so CString is actually a CStringW, i.e. TCHAR ==
wchar_t), but you want to output the string to the file using ASCII.
First thing: to be safe, you should be sure that the UTF-16 CString actually
stores only the proper ASCII subset (e.g. digits 0-9, American letters a-Z,
etc.).
In that case, I think that if you use CStdioFile class from MFC, even in
Unicode builds, your strings will be written as ASCII/MBCS.
However, you can do a conversion manually, using proper ATL conversion
helper classes, like CW2A. CW2A converts a Unicode ("wide" char) string to
an ASCII/ANSI string. You can use like this:
CW2A ansiString( utf16String );
and you can use 'ansiString' wherever a 'const char *' is expected (in fact,
there is an implicit conversion operator for const char* defined for CW2A
class).
The CW2A class uses RAII paradigma, so you don't have problems of properly
releasing the string. The class destructor will do proper cleanup for you.
Moreover, if you use CString in your code (and not CStringW), you may want
to use CT2A, which works fine also in ANSI builds (where TCHAR == char; in
this case basically no conversion happens):
CString myString;
...
CT2A ansiString( myString );
... write ansiString to file using e.g. C++ file output stream
Finally, as a general point, what is the difference between the Microsoft
Discussion groups and the MSDN forum?
Probably, with "Microsoft Discussion groups" you mean those NNTP based
newsgroups, instead with "MSDN forums" you mean the web-based forums?
Giovanni