How to split string using istringstream with other delimiter than whitespace?

Question

The following trick using istringstream to split a string with white spaces.

int main() {
    string sentence(\"Cpp is fun\");
    istringstream         


        

Answer 1

#include <iostream>
#include <string>
#include <sstream>

int main()
{
  std::istringstream iss { "Cpp|is|fun" };

  std::string s;
  while ( std::getline( iss, s, '|' ) )
    std::cout << s << std::endl;

  return 0;
}

Demo

Answer 2

The following code uses a regex to find the "|" and split the surrounding elements into an array. It then prints each of those elements, using cout, in a for loop.

This method allows for splitting with regex as an alternative.

#include <iostream>
#include <string>
#include <regex>
#include <algorithm>
#include <iterator>
    
using namespace std;


vector<string> splitter(string in_pattern, string& content){
    vector<string> split_content;

    regex pattern(in_pattern);
    copy( sregex_token_iterator(content.begin(), content.end(), pattern, -1),
    sregex_token_iterator(),back_inserter(split_content));  
    return split_content;
}
    
int main()
{   

    string sentence = "This|is|the|sentence";
    //vector<string> words = splitter(R"(\s+)", sentence); // seperate by space
    vector<string> words = splitter(R"(\|)", sentence);

    for (string word: words){cout << word << endl;}

}   

Answer 3

Generally speaking the istringstream approach is slow/inefficient and requires at least as much memory as the string itself (what happens when you have a very large string?). The C++ String Toolkit Library (StrTk) has the following solution to your problem:

#include <string>
#include <vector>
#include <deque>
#include "strtk.hpp"
int main()
{
   std::string sentence1( "Cpp is fun" );
   std::vector<std::string> vec;
   strtk::parse(sentence1," ",vec);

   std::string sentence2( "Cpp,is|fun" );
   std::deque<std::string> deq;
   strtk::parse(sentence2,"|,",deq);

   return 0;
}

More examples can be found Here