Compare string case insensitive

std::string provides a method std::string::find to search for the sub string inside a given string, but this function is case sensitive i.e.

Compare Two Strings by Ignoring Case in C#

Comparing strings in a case insensitive manner means to compare them without taking care of the uppercase and lowercase letters. To perform this operation the most preferred method is to use either toUpperCase() or toLowerCase() function . toUpperCase() function: The str.