How do I convert a UTF-8 string to upper case?

Question

Is there a portable way to convert a UTF-8 string in C to upper case? If not, what is the Linux way to do it?

Answer 1

The portable way of doing it would be to use a Unicode aware library such as ICU . Seems like u_strToUpper might the function you're looking for.

Answer 2

glib有g_utf8_strup() 。

Answer 3

The canonical way to do this is with wchar_t -- if you have a string of wide characters and use towlower/towupper/towctrans with your wide characters (which will work if your locale is set correctly). So you need to take your UTF-8 string, convert it into a wide-character string, and then use these functions that take wchar_t's and then convert back.

This is a giant PITA so you're probably better off using a supported, open-source Unicode library like ICU .