Why doesn't printf format unicode parameters?

Question

When using printf to format a double-byte string into a single-byte string:

printf(\"%ls\\n\", L\"s:\\\\яшертыHello\");   // %ls for a wide string (%s varies         


        

Answer 1

In C++ I usually use std::stringstream to create formatted text. I also implemented an own operator to use Windows function to make the encoding:

ostream & operator << ( ostream &os, const wchar_t * str )
{
  if ( ( str == 0 ) || ( str[0] == L'\0' ) )
   return os;
  int new_size = WideCharToMultiByte( CP_UTF8, 0, str, -1, NULL, NULL, NULL, NULL );
  if ( new_size <= 0 )
    return os;
  std::vector buffer(new_size);
  if ( WideCharToMultiByte( CP_UTF8, 0, str, -1, &buffer[0], new_size, NULL, NULL ) > 0 )
    os << &buffer[0];
  return os;
}

This code convert to UTF-8. For other possibilities check: WideCharToMultiByte.