Question

I´m looking for a regular expression in C++11 which can match a substring in a string.

Something like: "It´s a dark night out there..." and I´m searching for ark

So if a substring is somewhere in a string this expression shall match.
Furthermore i would like to have the option to say that this match should be case sensitive or not.

I´ve already tried this but it doesn´t seem to work…

string str = "It´s a dark night out there...";
regex ex ("ark"); 
if (regex_match (str,ex))
    cout << "Match found!";

Does anybody know something like that?

Answer 1

Use regex_search instead of regex_match. The latter tries to match the entire subject string, while the former allows to match substrings.

And here are the possible flags, one of which (the first) represents case-insensitive matching.