ANSI、UTF-8、UNICODE字符串相互转化

std::wstring AnsiToUnicode(const char* src)
{
if (src == NULL || src[0] == '\0')
{
return L"";
}
std::string strSrc(src);
int length = MultiByteToWideChar(CP_ACP, 0, strSrc.c_str(), -1, NULL, 0);
wchar_t *buf = new wchar_t[length + 1];
MultiByteToWideChar(CP_ACP, 0, strSrc.c_str(), -1, buf, length);
buf[length] = L'\0';
std::wstring dest = buf;
delete [] buf;
return dest;
}


std::string AnsiToUTF8(const char* src)
{
std::wstring unicode = AnsiToUnicode(src);
return UnicodeToUTF8(unicode.c_str());
}


std::string UTF8ToAnsi(const char* src)
{
std::wstring unicode = UTF8ToUnicode(src);
return UnicodeTochar(unicode.c_str());
}


std::wstring UTF8ToUnicode(const char* src)
{
if (src == NULL || src[0] == '\0')
{
return L"";
}
std::string strSrc(src);
int length = MultiByteToWideChar(CP_UTF8, 0, strSrc.c_str(), -1, NULL, 0);
wchar_t *buf = new wchar_t[length + 1];
MultiByteToWideChar(CP_UTF8, 0, strSrc.c_str(), -1, buf, length);
buf[length] = L'\0';
std::wstring dest = buf;
delete [] buf;
return dest;
}


std::string UnicodeToUTF8(const wchar_t* src)
{
if (src == NULL || src[0] == '\0')
{
return "";
}


std::wstring strSrc(src);
int length = WideCharToMultiByte(CP_UTF8, 0, strSrc.c_str(), 
-1, NULL, 0, NULL, FALSE);
char *buf = new char[length + 1];
WideCharToMultiByte(CP_UTF8, 0, strSrc.c_str(), -1, buf, length, NULL, FALSE);
buf[length] = '\0';
std::string dest = buf;
delete [] buf;
return dest;
}


tstring UTF8ToNative(const char* src)
{
#ifdef UNICODE
return UTF8ToUnicode(src);
#else
return UTF8ToAnsi(src);
#endif
}


std::string  NativeToUTF8(LPCTSTR src)
{
#ifdef UNICODE
return UnicodeToUTF8(src);
#else
return AnsiToUTF8(src);
#endif
}


std::wstring  TCHARToUnicode(LPCTSTR src)
{
if (src == NULL || src[0] == '\0')
{
return L"";
}
#ifdef UNICODE
return src;
#else
return AnsiToUnicode(src);
#endif
}


std::string UnicodeTochar(const wchar_t*src)
{
if (!src)
return "";


int unicode_len = wcslen(src);
int charcount = ::WideCharToMultiByte(CP_ACP, 0, src, unicode_len, NULL, 0, NULL, NULL);
if (charcount == 0)
return "";


std::string mb;
mb.resize(charcount);
::WideCharToMultiByte(CP_ACP, 0, src, unicode_len, &mb[0], charcount, NULL, NULL);


return mb;
}




bool UTF8ToUnicode(std::wstring& str_out,  const std::string& str_in)
{
int  len = str_in.length();
int  unicodeLen = MultiByteToWideChar( CP_UTF8,
0,
str_in.c_str(),
-1,
NULL,
0 ); 
if (unicodeLen <= 0){
return false;
}


wchar_t*  pUnicode = new  wchar_t[unicodeLen+1]; 
memset(pUnicode,0,(unicodeLen+1)*sizeof(wchar_t)); 


int ret = MultiByteToWideChar( CP_UTF8,
0,
str_in.c_str(),
-1,
(LPWSTR)pUnicode,
unicodeLen ); 
if (ret <= 0){
delete[] pUnicode;
return false;
}


str_out = ( wchar_t* )pUnicode;
delete[]  pUnicode;


return  true; 
}


bool UnicodeToUTF8(std::string& str_out, const std::wstring& str_in)
{
char* pElementText;
int  iTextLen;


iTextLen = WideCharToMultiByte( CP_UTF8,
0,
str_in.c_str(),
-1,
NULL,
0,
NULL,
NULL );
if (iTextLen <=0 ){
return false;
}


pElementText = new char[iTextLen + 1];
memset( ( void* )pElementText, 0, sizeof( char ) * ( iTextLen + 1 ) );
int ret = WideCharToMultiByte( CP_UTF8,
0,
str_in.c_str(),
-1,
pElementText,
iTextLen,
NULL,
NULL );


if (ret <= 0){
delete[] pElementText;
return false;
}


str_out= pElementText;
delete[] pElementText;
return true;
}


bool UnicodeToMulti(std::string& str_out, const std::wstring& str_in)
{
char* pElementText;
int  iTextLen;


iTextLen = WideCharToMultiByte( CP_ACP,
0,
str_in.c_str(),
-1,
NULL,
0,
NULL,
NULL );
if (iTextLen <=0 ){
return false;
}


pElementText = new char[iTextLen + 1];
memset( ( void* )pElementText, 0, sizeof( char ) * ( iTextLen + 1 ) );
int ret = WideCharToMultiByte( CP_ACP,
0,
str_in.c_str(),
-1,
pElementText,
iTextLen,
NULL,
NULL );


if (ret <= 0){
delete[] pElementText;
return false;
}


str_out= pElementText;
delete[] pElementText;
return true;
}


bool MultiToUnicode(std::wstring& str_out, const std::string& str_in)
{
int  len = str_in.length();
int  unicodeLen = MultiByteToWideChar( CP_ACP,
0,
str_in.c_str(),
-1,
NULL,
0 ); 
if (unicodeLen <= 0){
return false;
}


wchar_t*  pUnicode = new  wchar_t[unicodeLen+1]; 
memset(pUnicode,0,(unicodeLen+1)*sizeof(wchar_t)); 


int ret = MultiByteToWideChar( CP_ACP,
0,
str_in.c_str(),
-1,
(LPWSTR)pUnicode,
unicodeLen ); 
if (ret <= 0){
delete[] pUnicode;
return false;
}


str_out = ( wchar_t* )pUnicode;
delete[]  pUnicode;


return  true; 
}