string 与wstring 的转换

std::wstring StringToWString(const std::string &str)
{
std::wstring wstr(str.length(),L' ');
std::copy(str.begin(), str.end(), wstr.begin());
return wstr;
}

//只拷贝低字节至string中
std::string WStringToString(const std::wstring &wstr)
{
std::string str(wstr.length(), ' ');
std::copy(wstr.begin(), wstr.end(), str.begin());
return str;
}

上面的对于英文字符串 是正确的，对于中文是错误的，下面的代码则适用于中英文！

std::string AVentilationGraph::wstring2string(const std::wstring &wstr)
{
    std::string curLocale = setlocale(LC_ALL, NULL);        // curLocale = "C";
    setlocale(LC_ALL, "chs");
    const wchar_t* _Source = wstr.c_str();
    size_t _Dsize = 2 * wstr.size() + 1;
    char *_Dest = new char[_Dsize];
    memset(_Dest, 0, _Dsize);
    wcstombs(_Dest, _Source, _Dsize);
    std::string result = _Dest;
    delete[]_Dest;
    setlocale(LC_ALL, curLocale.c_str());
    return result;
}

//wstring 转 string
std::wstring AVentilationGraph::string2wstring(const std::string &str)
{
    setlocale(LC_ALL, "chs");
    const char* _Source = str.c_str();
    size_t _Dsize = str.size() + 1;
    wchar_t *_Dest = new wchar_t[_Dsize];
    wmemset(_Dest, 0, _Dsize);
    mbstowcs(_Dest, _Source, _Dsize);
    std::wstring result = _Dest;
    delete[]_Dest;
    setlocale(LC_ALL, "C");
    return result;
}