GB2312, BIG5, UTF8, Unicode之间的互换

char* UTF8ToGB2312(const char* pStrUTF8)
{
	// 先转成宽字符
	int nStrLen = MultiByteToWideChar(CP_UTF8, 0, pStrUTF8, -1, NULL, 0);
	wchar_t* pWStr = new wchar_t[nStrLen + 1];
	memset(pWStr, 0, nStrLen + 1);
	MultiByteToWideChar(CP_UTF8, 0, pStrUTF8, -1, pWStr, nStrLen);

	// 再转成GB2312
	nStrLen = WideCharToMultiByte(CP_ACP, 0, pWStr, -1, NULL, 0, NULL, NULL);
	char* pStr = new char[nStrLen + 1];
	memset(pStr, 0, nStrLen + 1);
	WideCharToMultiByte(CP_ACP, 0, pWStr, -1, pStr, nStrLen, NULL, NULL);
	if(pWStr)
	{
		delete[] pWStr;
	}
	return pStr;
}


char* GB2312ToUTF8(const char* pStrGB2312)
{
	// 先转成宽字符
	int nStrLen = MultiByteToWideChar(CP_ACP, 0, pStrGB2312, -1, NULL, 0);
	wchar_t* pWStr = new wchar_t[nStrLen + 1];
	memset(pWStr, 0, nStrLen + 1);
	MultiByteToWideChar(CP_ACP, 0, pStrGB2312, -1, pWStr, nStrLen);

	// 再转为UTF8
	nStrLen = WideCharToMultiByte(CP_UTF8, 0, pWStr, -1, NULL, 0, NULL, NULL);
	char* pStr = new char[nStrLen + 1];
	memset(pStr, 0, nStrLen + 1);
	WideCharToMultiByte(CP_UTF8, 0, pWStr, -1, pStr, nStrLen, NULL, NULL);
	if(pWStr)
	{
		delete[] pWStr;
	}
	return pStr;
}

这个更精简

// GB2312, BIG5, UTF8之间的转换通过Unicode充当切换的桥梁
// 例如: GB2312<->Unicode<->BIG5

#define CODEPAGE_GB2312		936
#define CODEPAGE_BIG5		950 
#define CODEPAGE_UTF8		65001

// 转换成Unicode
wchar_t* ToWideChar(const char* pStr, int nCodePage)
{
	int nStrLen = MultiByteToWideChar(nCodePage, 0, pStr, -1, NULL, 0);
	wchar_t* pWStr = new wchar_t[nStrLen + 1];
	memset(pWStr, 0, nStrLen + 1);
	MultiByteToWideChar(nCodePage, 0, pStr, -1, pWStr, nStrLen);
	return pWStr;
}

// 转换成多字节
char* ToMultiByte(const wchar_t* pWStr, int nCodePage)
{
	int nStrLen = WideCharToMultiByte(nCodePage, 0, pWStr, -1, NULL, 0, NULL, NULL);
	char* pStr = new char[nStrLen + 1];
	memset(pStr, 0, nStrLen + 1);
	WideCharToMultiByte(nCodePage, 0, pWStr, -1, pStr, nStrLen, NULL, NULL);
	return pStr;
}

char* CPTransform(const char* pStrSrc, int nCPSrc, int nCPTar)
{
	wchar_t* pWStr = ToWideChar(pStrSrc, nCPSrc);
	char* pStr = ToMultiByte(pWStr, nCPTar);
	delete [] pWStr;
	return pStr;
}

// GB2312转UTF8
char* GB2312ToUTF8(const char* pStrGB2312)
{
	return CPTransform(pStrGB2312, CODEPAGE_GB2312, CODEPAGE_UTF8);
}

// UTF8转GB2312
char* UTF8ToGB2312(const char* pStrUTF8)
{
	return CPTransform(pStrUTF8, CODEPAGE_UTF8, CODEPAGE_GB2312);
}

// GB2312转BIG5
char* GB2312ToBIG5(const char* pStrBIG5)
{
	return CPTransform(pStrBIG5, CODEPAGE_GB2312, CODEPAGE_BIG5);
}

// BIG5转GB2312
char* BIG5ToGB2312(const char* pStrBIG5)
{
	return CPTransform(pStrBIG5, CODEPAGE_BIG5, CODEPAGE_GB2312);
}

// UTF8转BIG5
char* UTF8ToBIG5(const char* pStrUTF8)
{
	return CPTransform(pStrUTF8, CODEPAGE_UTF8, CODEPAGE_BIG5);
}

// BIG5转UTF8
char* BIG5ToUTF8(const char* pStrBIG5)
{
	return CPTransform(pStrBIG5, CODEPAGE_BIG5, CODEPAGE_UTF8);
}

返回的cha* 指针需要调用者自行删除

注意: UTF8和GB2312都是使用char* 表示的

编码了解:  http://blog.csdn.net/bagboy_taobao_com/article/details/42294097