多字节编码转为UTF8编码 & UTF8编码转为多字节

开发环境：VS2008

#include <iostream>

#include <windows.h>

#include <string>

void ConvertGBKToUtf8(std::string& amp, std::string strGBK)

{ 
int len=MultiByteToWideChar(CP_ACP, 0, (LPCSTR)strGBK.c_str(), -1, NULL,0); 
unsigned short * wszUtf8 = new unsigned short[len+1]; 
memset(wszUtf8, 0, len * 2 + 2); 
MultiByteToWideChar(CP_ACP, 0, (LPCSTR)strGBK.c_str(), -1, (LPWSTR)wszUtf8, len); 
len = WideCharToMultiByte(CP_UTF8, 0, (LPCWSTR)wszUtf8, -1, NULL, 0, NULL, NULL); 
char *szUtf8=new char[len + 1]; 
memset(szUtf8, 0, len + 1); 
WideCharToMultiByte (CP_UTF8, 0, (LPCWSTR)wszUtf8, -1, szUtf8, len, NULL,NULL); 
//strGBK = szUtf8; 
amp=szUtf8;
delete[] szUtf8; 
delete[] wszUtf8; 

}

void ConvertUtf8ToGBK(std::string&, std::string strUtf8)

{ 
int len=MultiByteToWideChar(CP_UTF8, 0, (LPCSTR)strUtf8.c_str(), -1, NULL,0); 
unsigned short * wszGBK = new unsigned short[len+1]; 
memset(wszGBK, 0, len * 2 + 2); 
MultiByteToWideChar(CP_UTF8, 0, (LPCSTR)strUtf8.c_str(), -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; 
amp=szGBK;
delete[] szGBK; 
delete[] wszGBK; 

}

int main(int argc, char *argv)

{
std::string amp;
std::string strGBK = "china 中国人民！！";
ConvertGBKToUtf8(amp, strGBK);

std::wcout << "/////////////////////////////////// " << std::endl;

std::string temp;
ConvertUtf8ToGBK(temp, amp);
std::cout << "Utf8ToGBK : " << temp << std::endl;
system("PAUSE");

}