Wrong filename when using chinese characters - c++

Question

I'm trying to create a file on Windows using a Chinese character. The entire path is inside the variable "std::string originalPath", however, I have a charset problem that I simply cannot understand to overcome.
I have written the following code:
#include <iostream>
#include <boost/locale.hpp>
#include <boost/filesystem/fstream.hpp>
#include <windows.h>
int main( int argc, char *argv[] )
{
// Start the rand
srand( time( NULL ) );
// Create and install global locale
std::locale::global( boost::locale::generator().generate( "" ) );
// Make boost.filesystem use it
boost::filesystem::path::imbue( std::locale() );
// Check if set to utf-8
if( std::use_facet<boost::locale::info>( std::locale() ).encoding() != "utf-8" ){
std::cerr << "Wrong encoding" << std::endl;
return -1;
}
std::string originalPath = "C:/test/s/一.png";
// Convert to wstring (**WRONG!**)
std::wstring newPath( originalPath.begin(), originalPath.end() );
LPWSTR lp=(LPWSTR )newPath.c_str();
CreateFileW(lp,GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ |
FILE_SHARE_WRITE, NULL,CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL );
return 0;
}
Running it, however, I get inside the folder "C:\test\s" a file of name "￤ﾸﾀ.png", instead of "一.png", which I want. The only way I found to overcome this is to exchange the lines
std::string originalPath = "C:/test/s/一.png";
// Convert to wstring (**WRONG!**)
std::wstring newPath( originalPath.begin(), originalPath.end() );
to simply
std::wstring newPath = L"C:/test/s/一.png";
In this case the file "一.png" appears perfectly inside the folder "C:\test\s". Nonetheless, I cannot do that because the software get its path from a std::string variable. I think the conversion from std::string to std::wstring is being performed the wrong way, however, as it can be seen, I'm having deep problem trying to understand this logic. I read and researched Google exhaustively, read many qualitative texts, but all my attempts seem to be useless. I tried the MultiByteToWideChar function and also boost::filesystem, but both for no help, I simply cannot get the right filename when written to the folder.
I'm still learning, so I'm very sorry if I'm making a dumb mistake. My IDE is Eclipse and it is set up to UTF-8.

Answer 1

You need to actually convert the UTF-8 string to UTF-16. For that you have to look up how to use boost::locale::conv or (on Windows only) the MultiByteToWideChar function.
std::wstring newPath( originalPath.begin(), originalPath.end() ); won't work, it will simply copy all the bytes one by one and cast them to a wchar_t.

Answer 2

Thank you for your help, roeland. Finally I managed to find a solution and I simply used this following library: "http://utfcpp.sourceforge.net/". I used the function "utf8::utf8to16" to convert my original UTF-8 string to UTF-16, this way allowing Windows to display the Chinese characters correctly.