不同编码之间的转换（UTF-8,UNICODE,多字节，宽字节）

BOOL CUtils::CharToWchar(std::string src, std::wstring& dest)
{
    int dwMinSize = MultiByteToWideChar(CP_ACP, MB_PRECOMPOSED, src.c_str(), -1, NULL, 0);

    if (dwMinSize == 0)
    {
        return 0;
    }
    dest.resize(dwMinSize);

    int nlen = MultiByteToWideChar(CP_ACP, MB_PRECOMPOSED, src.c_str(), -1, &dest.at(0), dwMinSize);
    return nlen > 0;
}

BOOL CUtils::WcharToChar(std::wstring src, std::string& dest)
{
    int dwMinSize = WideCharToMultiByte(CP_ACP, NULL, src.c_str(), -1, NULL, 0, NULL, FALSE);
    if (dwMinSize == 0)
    {
        return 0;
    }

    dest.resize(dwMinSize);

    int nlen = WideCharToMultiByte(CP_ACP, NULL, src.c_str(), -1, &dest.at(0), dwMinSize, NULL, FALSE);
    return nlen > 0;
}

BOOL CUtils::UTF8ToWchar(std::string src, std::wstring& dest)
{
    //预转换，得到所需空间的大小;
    int wcsLen = ::MultiByteToWideChar(CP_UTF8, NULL, src.c_str(), src.size(), NULL, 0);
    if (wcsLen == 0)
    {
        return 0;
    }
    dest.resize(wcsLen);
    int nLen = ::MultiByteToWideChar(CP_UTF8, NULL, src.c_str(), src.size(), &dest.at(0), wcsLen);

    return wcsLen > 0;
}

BOOL CUtils::WcharToUTF8(std::wstring src, std::string& dest)
{
    int dwMinSize = WideCharToMultiByte(CP_UTF8, NULL, src.c_str(), -1, NULL, 0, NULL, FALSE);
    if (dwMinSize == 0)
    {
        return 0;
    }

    dest.resize(dwMinSize);

    int nLen = WideCharToMultiByte(CP_UTF8, 0, src.c_str(), -1, &dest.at(0), dwMinSize, NULL, NULL);
    return nLen > 0;
}