UTF-8和Unicode互转

1、Unicode转UTF-8

 void CodeCovertTool::UNICODE_to_UTF8(const CString& unicodeString, std::string& str)
 {//Unicode转UTF8
     int stringLength = ::WideCharToMultiByte(CP_UTF8, NULL, unicodeString, wcslen(unicodeString), NULL, , NULL, NULL);

     char* buffer = new char[stringLength + ];
     ::WideCharToMultiByte(CP_UTF8, NULL, unicodeString, wcslen(unicodeString), buffer, stringLength, NULL, NULL);
     buffer[stringLength] = '\0';

     str = buffer;

     delete[] buffer;
 }

 std::string CodeCovertTool::UnicodeToUtf8(const wchar_t* buf)
 {//Unicode转UTF8
     int len = ::WideCharToMultiByte(CP_UTF8, , buf, -, NULL, , NULL, NULL);
     if (len == ) return "";  

     std::vector<char> utf8(len);
     ::WideCharToMultiByte(CP_UTF8, , buf, -, &utf8[], len, NULL, NULL);  

     return &utf8[];
 }  

2、UTF-8转Unicode

 std::wstring CodeCovertTool::Utf8ToUnicode(const char* buf)
 {//UTF8转Unicode
     int len = ::MultiByteToWideChar(CP_UTF8, , buf, -, NULL, );
     if (len == ) return _T("");  

     std::vector<wchar_t> unicode(len);
     ::MultiByteToWideChar(CP_UTF8, , buf, -, &unicode[], len);  

     return &unicode[];
 }  

 CString CodeCovertTool::Utf8ToUnicode(const std::string &utf8_str)
 {//UTF8转Unicode
     int len;
     len = MultiByteToWideChar(CP_UTF8, , (LPCSTR)utf8_str.c_str(), -, NULL,);
     WCHAR * wszUnicode = new WCHAR[len+];
     memset(wszUnicode, , len *  + );
     MultiByteToWideChar(CP_UTF8, , (LPCSTR)utf8_str.c_str(), -, wszUnicode, len);
     CString ss=wszUnicode;
     delete wszUnicode;
     return ss;
 }

3、Ansi转Unicode

 std::wstring CodeCovertTool::AnsiToUnicode(const char* buf)
 {//Ansi转Unicode
     int len = ::MultiByteToWideChar(CP_ACP, , buf, -, NULL, );
     if (len == ) return L"";  

     std::vector<wchar_t> unicode(len);
     ::MultiByteToWideChar(CP_ACP, , buf, -, &unicode[], len);  

     return &unicode[];
 }

4、Unicode转Ansi

 std::string CodeCovertTool::UnicodeToAnsi(const wchar_t* buf)
 {//Unicode转Ansi
     int len = ::WideCharToMultiByte(CP_ACP, , buf, -, NULL, , NULL, NULL);
     if (len == ) return "";  

     std::vector<char> utf8(len);
     ::WideCharToMultiByte(CP_ACP, , buf, -, &utf8[], len, NULL, NULL);  

     return &utf8[];
 }