How to show Cyrillic text in MFC Multi-Byte application? - c++

Question

I am new with C++ and MFC. The main problem is that I have an MFC project that needs to be translated into Russian. I see that the best option is to change the project to Unicode but I cannot, because it is a huge project and when I change I receive more than 4000 errors. Later we will pass all the code to Unicode, but for now I just need to show Cyrillic on the buttons and CListBox.
Well, the main thing is: How to print Cyrillic with Multibyte?
Thanks guys!
PD: Sorry, I am gonna be more explicit with what I tried:
Use russian locales:
setlocale(LC_ALL, "russian_russia.1251");
setlocale(LC_CTYPE, "rus");
But didn't work. Shows question marks.
Also I tried to convert with function WideCharToMultiByte. But shows characters that seems to be encoded wrong.
std::string utf8_encode(const std::wstring &wstr)
{
if (wstr.empty()) return std::string();
int size_needed = WideCharToMultiByte(CP_UTF8, 0, &wstr[0], (int)wstr.size(), NULL, 0, NULL, NULL);
std::string strTo(size_needed, 0);
WideCharToMultiByte(CP_UTF8, 0, &wstr[0], (int)wstr.size(), &strTo[0], size_needed, NULL, NULL);
return strTo;
}
wchar_t* wch = L"Привет";
std::string ch = utf8_encode(wch);
m_wndOutputBuild.AddString(ch.c_str()); //OUTPUT Привет
PD2: Now I call like this
setlocale(LC_ALL, "russian_russia.1251");
std::wstring wch = L"Привет";
std::string ch = encode_1251(wch);
m_wndOutputBuild.AddString(ch.c_str()); //OUTPUT Ïðèâåò
and Function:
std::string encode_1251(const std::wstring &wstr)
{
if (wstr.empty()) return std::string();
int size_needed = WideCharToMultiByte(1251, 0, &wstr[0], (int)wstr.size(), NULL, 0, NULL, NULL);
std::string strTo(size_needed, 0);
WideCharToMultiByte(1251, 0, &wstr[0], (int)wstr.size(), &strTo[0], size_needed, NULL, NULL);
return strTo;
}
I found that Windows-1251 puts CP like that on WideCharToMultiByte here.

Answer 1

In your utf8_encode function, when converting your Unicode UTF-16 string to a std::string, you passed CP_UTF8 to WideCharToMultiByte. Then you take the returned UTF-8 std::string, and pass it via .c_str() to the CListBox::AddString method.
However, if your application is in MBCS Cyrillic, you should convert from UTF-16 to your Cyrillic code page, instead of UTF-8, and pass the strings encoded in your Cyrillic code page to your MFC class methods, like CListBox::AddString.
In other words, you may want to substitute your utf8_encode function with a cyrillic_encode function, that takes UTF-16 text as input, and converts it to your Cyrillic code page:
// Convert from Unicode UTF-16 to Cyrillic code page
std::string cyrillic_encode(const std::wstring &utf16)
And then pass the returned string to the MFC class methods of interest, e.g.:
// From Unicode UTF-16 to Cyrillic code page
std::string cyrillic_text = cyrillic_encode(wch);
// Show Cyrillic-encoded "MBCS" text
m_wndOutputBuild.AddString(cyrillic_text.c_str());
Moreover, as correctly pointed out by #IInspectable in the comments, consider adding proper error checking code in your conversion functions. In fact, in general, there can be UTF-16 text that cannot be properly encoded in Cyrillic, as the latter is a proper subset of the former.