void ConvertGBKToUtf8(CString& strGBK) {
    int len=MultiByteToWideChar(CP_ACP, 0, (LPCTSTR)strGBK, -1, NULL,0);
    unsigned short * wszUtf8 = new unsigned short[len+1];
    memset(wszUtf8, 0, len * 2 + 2);
    MultiByteToWideChar(CP_ACP, 0, (LPCTSTR)strGBK, -1, wszUtf8, len);

len = WideCharToMultiByte(CP_UTF8, 0, wszUtf8, -1, NULL, 0, NULL, NULL);
    char *szUtf8=new char[len + 1];
    memset(szUtf8, 0, len + 1);
    WideCharToMultiByte (CP_UTF8, 0, wszUtf8, -1, szUtf8, len, NULL,NULL);

strGBK = szUtf8;
    delete[] szUtf8;
    delete[] wszUtf8;
}

void ConvertUtf8ToGBK(CString& strUtf8) {
    int len=MultiByteToWideChar(CP_UTF8, 0, (LPCTSTR)strUtf8, -1, NULL,0);
    unsigned short * wszGBK = new unsigned short[len+1];
    memset(wszGBK, 0, len * 2 + 2);
    MultiByteToWideChar(CP_UTF8, 0, (LPCTSTR)strUtf8, -1, wszGBK, len);

len = WideCharToMultiByte(CP_ACP, 0, wszGBK, -1, NULL, 0, NULL, NULL);
    char *szGBK=new char[len + 1];
    memset(szGBK, 0, len + 1);
    WideCharToMultiByte (CP_ACP, 0, wszGBK, -1, szGBK, len, NULL,NULL);

strUtf8 = szGBK;
    delete[] szGBK;
    delete[] wszGBK;
}