Changing cases and case-insensitive comparison

This is a pretty common task. We have two non-Unicode or ANSI character strings:

#include <string> 
std::string str1 = "Thanks for reading me!"; 
std::string str2 = "Thanks for reading ME!"; 

We need to compare them in a case-insensitive manner. There are a lot of methods to do that, let's take a look at Boost's.

Getting ready

Basic knowledge of std::string is all we need here.

How to do it...

Here are different ways to do case-insensitive comparisons:

1. The most simple one is:

#include <boost/algorithm/string/predicate.hpp> 

const bool solution_1 = (
     boost::iequals(str1, str2)
);

2. Using the Boost predicate and standard library method:

#include <boost/algorithm/string/compare.hpp> 
#include <algorithm> 

const bool solution_2 = (
    str1.size() == str2.size() && std::equal(
        str1.begin(),
        str1.end(),
        str2.begin(),
        boost::is_iequal()
    )
);

3. Making a lowercase copy of both the strings:

...