Read a string line by line using c++

I have a std::string with multiple lines and I need to read it line by line. Please show me how to do it with a small example.

Ex: I have a string string h;

h will be:

Hello there.
How are you today?
I am fine, thank you.

I need to extract Hello there., How are you today?, and I am fine, thank you. somehow.

#include <sstream>
#include <iostream>

int main() {
    std::istringstream f("line1\nline2\nline3");
    std::string line;    
    while (std::getline(f, line)) {
        std::cout << line << std::endl;
    }
}

There are several ways to do that.

You can use std::string::find in a loop for '\n' characters and substr() between the positions.

You can use std::istringstream and std::getline( istr, line ) (Probably the easiest)

You can use boost::tokenize

this would help you : http://www.cplusplus.com/reference/iostream/istream/getline/