Question

i want to extract all dash separated digits ( like this 232-65 ) from string in c++ using boost regex
i use this pattern

\\d*-\\d*

but only first match is detected. what should i do to extract all matched pattern.

example input :

"2 1 5-25 37 42 43 53 69-119 123-514"

out put is only 5-25 but must be 5-25 69-119 123-514

my sample code is

    cmatch res;

boost::regex port("\\d*-\\d*");

regex_search(s,res, port);

for (unsigned int i = 0; i < res.size(); ++i) {
    cout << res[i] << endl;
}

Answer 1

This is for C++11, but you should be able to replace the std:: with boost:: to make it work with Boost

std::string s = std::string("2 1 5-25 37 42 43 53 69-119 123-514");

std::regex port("\\d*-\\d*");
std::sregex_token_iterator iter(s.begin(), s.end(), port);
std::sregex_token_iterator end;

for(; iter != end; ++iter) 
{
    std::cout << iter->str() << std::endl;
}

Taken from Boost C++ regex – how to get multiple matches

If you want to use const char* it should be:

const char *s = "2 1 5-25 37 42 43 53 69-119 123-514";

std::regex port("\\d*-\\d*");
std::cregex_token_iterator iter(s, s + strlen(s), port);
std::cregex_token_iterator end;

for(; iter != end; ++iter) 
{
    std::cout << iter->str() << std::endl;
}