Question

What is the best way of doing case-insensitive string comparison in C++ without transforming a string to all uppercase or all lowercase?

Please indicate whether the methods are Unicode-friendly and how portable they are.

Answer 1

Boost includes a handy algorithm for this:

#include <boost/algorithm/string.hpp> // Or, for fewer header dependencies: //#include <boost/algorithm/string/predicate.hpp>  std::string str1 = 'hello, world!'; std::string str2 = 'HELLO, WORLD!';  if (boost::iequals(str1, str2)) {     // Strings are identical }