utf-8与GBK互转

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, (LPWSTR)wszGBK, len);

	len = WideCharToMultiByte(CP_ACP, 0, (LPCWSTR)wszGBK, -1, NULL, 0, NULL, NULL);
	char *szGBK=new char[len + 1];
	memset(szGBK, 0, len + 1);
	WideCharToMultiByte (CP_ACP, 0, (LPCWSTR)wszGBK, -1, szGBK, len, NULL,NULL);
	strUtf8 = szGBK;
	delete[] szGBK;
	delete[] wszGBK;
}

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;
}