c++ 字符串工具类

#include <iostream>

#include <vector>

using namespace std;





namespace strtool

{

string trim(const string& str)

{

    string::size_type pos = str.find_first_not_of(' ');

    if (pos == string::npos)

    {

        return str;

    }

    string::size_type pos2 = str.find_last_not_of(' ');

    if (pos2 != string::npos)

    {

        return str.substr(pos, pos2 - pos + 1);

    }

    return str.substr(pos);

}



int split(const string& str, vector<string>& ret_, string sep = ",")

{

    if (str.empty())

    {

        return 0;

    }



    string tmp;

    string::size_type pos_begin = str.find_first_not_of(sep);

    string::size_type comma_pos = 0;



    while (pos_begin != string::npos)

    {

        comma_pos = str.find(sep, pos_begin);

        if (comma_pos != string::npos)

        {

            tmp = str.substr(pos_begin, comma_pos - pos_begin);

            pos_begin = comma_pos + sep.length();

        }

        else

        {

            tmp = str.substr(pos_begin);

            pos_begin = comma_pos;

        }



        if (!tmp.empty())

        {

            ret_.push_back(tmp);

            tmp.clear();

        }

    }

    return 0;

}



string replace(const string& str, const string& src, const string& dest)

{

    string ret;



    string::size_type pos_begin = 0;

    string::size_type pos       = str.find(src);

    while (pos != string::npos)

    {

        cout <<"replacexxx:" << pos_begin <<" " << pos <<"\n";

        ret.append(str.data() + pos_begin, pos - pos_begin);

        ret += dest;

        pos_begin = pos + 1;

        pos       = str.find(src, pos_begin);

    }

    if (pos_begin < str.length())

    {

        ret.append(str.begin() + pos_begin, str.end());

    }

    return ret;

}



}









int main(int argc, char* argv[])

{

    cout << strtool::trim(" nihao ") <<"\n";



    vector<string> vt;

    strtool::split(",o h,,,nice,,,,,,,", vt);

    for (size_t i = 0; i < vt.size(); ++ i)

    {

        cout <<"out:" << vt[i] <<"\n";

    }



    string ret = strtool::replace("xxAxxxAxxAxx", "A", "B");

    cout <<"replace:" << ret <<"\n";

    return 0;

}