C++ Boost Library Cheat Sheet

#include <boost/filesystem.hpp>namespace fs = boost::filesystem;fs::path p = "/tmp/data/file.txt";std::cout << p.filename() << "\n";     // file.txtstd::cout << p.extension() << "\n";    // .txtstd::cout << p.parent_path() << "\n";  // /tmp/dataif (!fs::exists(p.parent_path())) {    fs::create_directories(p.parent_path());}for (auto& entry : fs::directory_iterator("/tmp/data")) {    std::cout << entry.path() << "\n";}

#include <boost/algorithm/string.hpp>std::string s = "  Hello, World!  ";boost::trim(s);                              // "Hello, World!"boost::to_lower(s);                          // "hello, world!"std::vector<std::string> parts;boost::split(parts, s, boost::is_any_of(",")); // split on commabool starts = boost::starts_with(s, "hello");std::string joined = boost::join(parts, "-");

#include <boost/asio.hpp>using boost::asio::ip::tcp;boost::asio::io_context io;tcp::resolver resolver(io);auto endpoints = resolver.resolve("example.com", "80");tcp::socket socket(io);boost::asio::connect(socket, endpoints);std::string request = "GET / HTTP/1.1\r\nHost: example.com\r\n\r\n";boost::asio::write(socket, boost::asio::buffer(request));boost::asio::streambuf response;boost::asio::read_until(socket, response, "\r\n");

#include <boost/optional.hpp>#include <boost/lexical_cast.hpp>boost::optional<int> parseInt(const std::string& s) {    try {        return boost::lexical_cast<int>(s);    } catch (const boost::bad_lexical_cast&) {        return boost::none;    }}if (auto value = parseInt("42")) {    std::cout << *value;      // 42}