GBK到UTF8编码转换的C++实现

std::string GBKToUTF8(const std::string& strGBK)
{
WCHAR * str1;
int n = MultiByteToWideChar(CP_ACP, 0, strGBK.c_str(), -1, NULL, 0);
str1 = new WCHAR
;
MultiByteToWideChar(CP_ACP, 0, strGBK.c_str(), -1, str1, n);
n = WideCharToMultiByte(CP_UTF8, 0, str1, -1, NULL, 0, NULL, NULL);
char * str2 = new char
;
WideCharToMultiByte(CP_UTF8, 0, str1, -1, str2, n, NULL, NULL);
std::string strOutUTF8;
strOutUTF8.assign(str2,n);
delete[]str1;
str1 = NULL;
delete[]str2;
str2 = NULL;
return strOutUTF8;
}

std::string UTF8ToGBK(const std::string& strUTF8)
{
int len = MultiByteToWideChar(CP_UTF8, 0, strUTF8.c_str(), -1, NULL, 0);
WCHAR* wszGBK = new WCHAR[len + 1];
memset(wszGBK, 0, len * 2 + 2);
MultiByteToWideChar(CP_UTF8, 0, (LPCTSTR)strUTF8.c_str(), -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;
std::string strTemp;
strTemp.assign(szGBK,len);
delete[]szGBK;
delete[]wszGBK;
return strTemp;
}