Case-insensitive string comparison in C++ [closed]

Answer 1

I'm trying to cobble together a good answer from all the posts, so help me edit this:

Here is a method of doing this, although it does transforming the strings, and is not Unicode friendly, it should be portable which is a plus:

bool caseInsensitiveStringCompare( const std::string& str1, const std::string& str2 ) {
    std::string str1Cpy( str1 );
    std::string str2Cpy( str2 );
    std::transform( str1Cpy.begin(), str1Cpy.end(), str1Cpy.begin(), ::tolower );
    std::transform( str2Cpy.begin(), str2Cpy.end(), str2Cpy.begin(), ::tolower );
    return ( str1Cpy == str2Cpy );
}

From what I have read this is more portable than stricmp() because stricmp() is not in fact part of the std library, but only implemented by most compiler vendors.

To get a truly Unicode friendly implementation it appears you must go outside the std library. One good 3rd party library is the IBM ICU (International Components for Unicode)

Also boost::iequals provides a fairly good utility for doing this sort of comparison.