Wrong encoding when getting a string from MySQL database with C++ - c++

Question

I'm writing an MFC app with C++ in Visual Studio 2012. App connects to a MySQL database and shows every row to a List Box.
Words are in Russian, database encoding is cp1251. I've set the same character set using this code:
if (!mysql_set_character_set(mysql, "cp1251")) {
statusBox.SetWindowText((CString)"CP1251 is set for MYSQL.");
}
But it doesn't help at all.
I display data using this code:
while ((row = mysql_fetch_row(result)) != NULL) {
CString string = (CString)row[1];
listBox.AddString(string);
}
This code also doesn't help:
mysql_query(mysql, "set names cp1251");
Please help. What should I do to display cyrillic correctly?

Answer 1

When crossing system boundaries that use different character encodings you have to convert between them. In this case, the MySQL database uses CP 1251 while Windows (and CString) use UTF-16. The conversion might look like this:
#if !defined(_UNICODE)
#error Unicode configuration required
#endif
CString CPtoUnicode( const char* CPString, UINT CodePage ) {
CString retValue;
// Retrieve required string length
int len = MultiByteToWideChar( CodePage, 0,
CPString, -1,
NULL, 0 );
if ( len == 0 ) {
// Error -> return empty string
return retValue;
}
// Allocate CString's internal buffer
LPWSTR buffer = retValue.GetBuffer( len );
// Do the conversion
MultiByteToWideChar( CodePage, 0,
CPString, -1,
buffer, len );
// Return control of the buffer back to the CString object
retValue.ReleaseBuffer();
return retValue;
}
This should be used as follows:
while ( ( row = mysql_fetch_row( result ) ) != NULL ) {
CString string = CPtoUnicode( row[1], 1251 );
listBox.AddString( string );
}
Alternatively, you could use CStrings built-in conversion support, which requires to set the thread's locale to the source encoding (CP 1251) and use the conversion constructor.