C++ 字符串处理4-根据指定的分隔符将字符串分割为多个子串&根据指定的分隔符将多个子串连接成一个字符串

#pragma once

#include <string>
#include <vector>

namespace cutl
{
    /**
     * @brief The type of vector strings used in this library.
     *
     */
    using strvec = std::vector<std::string>;

    /**
     * @brief Split a string into a vector of substrings using a given separator.
     *
     * @param str the string to be split.
     * @param separator the separator to split the string.
     * @return strvec the vector of substrings.
     */
    strvec split(const std::string &str, const std::string &separator);


    /**
     * @brief Join a vector of strings into a single string using a given separator.
     *
     * @param strlist the vector of strings to be joined.
     * @param separator the separator to join the strings.
     * @return std::string the joined string.
     */
    std::string join(const strvec &strlist, const std::string &separator = "");
} // namespace cutl

#include <cctype>
#include <algorithm>
#include "strutil.h"

namespace cutl
{
    strvec split(const std::string &str, const std::string &pattern)
    {
        strvec res;
        if (str == "")
            return res;
        // 在字符串末尾也加入分隔符，方便截取最后一段
        std::string strs = str + pattern;
        size_t pos = strs.find(pattern);
        int startIndex = 0;

        while (pos != strs.npos)
        {
            std::string temp = strs.substr(startIndex, pos - startIndex);
            res.emplace_back(temp);
            startIndex = pos + 1;
            pos = strs.find(pattern, startIndex);
        }

        return res;
    }

    std::string join(const strvec &strlist, const std::string &separator)
    {
        std::string text;
        for (size_t i = 0; i < strlist.size(); i++)
        {
            text += strlist[i];
            if (i < strlist.size() - 1)
            {
                text += separator;
            }
        }

        return text;
    }
} // namespace cutl

#include "common.hpp"
#include "strutil.h"

void TestJoinSplit()
{
    PrintSubTitle("TestJoinSplit");

    // split
    std::string fruits = "apple, banana, orange, pear";
    std::cout << "fruits: " << fruits << std::endl;
    auto fruits_vec = cutl::split(fruits, ",");
    std::cout << "list fruits item:" << std::endl;
    for (size_t i = 0; i < fruits_vec.size(); i++)
    {
        auto item = fruits_vec[i];
        auto fruit = cutl::strip(item);
        std::cout << item << ", after strip:" << fruit << std::endl;
        fruits_vec[i] = fruit;
    }
    // join
    std::cout << "join fruits with comma: " << cutl::join(fruits_vec, "; ") << std::endl;
}