C++ 使用STL string 实现的split,trim,replace

实现string 的去除两边空格,按指定字符截取,替换

#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;
}

posted @ 2012-01-15 23:15  海乐学习  阅读(8983)  评论(2编辑  收藏