Read and Write files of different encoding formats

BOOL CStdioFileEx::ReadString(CString& rString){const intnMAX_LINE_CHARS = 4096;BOOLbReadData = FALSE;LPTSTRlpsz;intnLen = 0;wchar_t*pszUnicodeString = NULL;wchar_t*pszMultiByteString= NULL;intnChars = 0;try{// If at position 0, discard byte-order mark before readingif (!m_pStream || (GetPosition() == 0 && m_bIsUnicodeText)){wchar_tcDummy;//Read(&cDummy, sizeof(_TCHAR));Read(&cDummy, sizeof(wchar_t));}// If compiled for Unicode#ifdef _UNICODEif (m_bIsUnicodeText){// Do standard stuff - Unicode to Unicode. Seems to work OK.bReadData = CStdioFile::ReadString(rString);}else{   //MultiByte(ASCII)--WideChar(UNICODE)pszUnicodeString= new wchar_t[nMAX_LINE_CHARS]; pszMultiByteString  = new wchar_t[nMAX_LINE_CHARS]; // Initialise to something safememset(pszUnicodeString, 0, sizeof(wchar_t) * nMAX_LINE_CHARS);memset(pszMultiByteString, 0, sizeof(wchar_t) * nMAX_LINE_CHARS);// Read the string from the file pointer to a temporary array//bReadData = (NULL != fgetws(pszMultiByteString, nMAX_LINE_CHARS, m_pStream));char *pszTemp=new char[nMAX_LINE_CHARS];ZeroMemory(pszTemp,nMAX_LINE_CHARS);    bReadData=(NULL != fgets(pszTemp, nMAX_LINE_CHARS, m_pStream));/*if(fgets( pszTemp, nMAX_LINE_CHARS, m_pStream )==NULL){bReadData=0;}else{bReadData=1;}*///open the file of UTF_8 and change to the UNICODE default coding            MultiByteToWideChar( CP_UTF8, 0, pszTemp, /*sizeof(pszTemp)*/ -1, pszMultiByteString, nMAX_LINE_CHARS );delete [] pszTemp;            //bReadData = (NULL != fgetws(pszMultiByteString, nMAX_LINE_CHARS, m_pStream));//if (bReadData)//{// Convert multibyte to Unicode, using the specified code page//nChars = GetUnicodeStringFromMultiByteString((LPCSTR)pszMultiByteString, pszUnicodeString, nMAX_LINE_CHARS, m_nFileCodePage);memcpy( pszUnicodeString, pszMultiByteString, sizeof(wchar_t) * nMAX_LINE_CHARS );//if (nChars > 0)//{rString = (CString)pszUnicodeString;//}//}}#elseif (!m_bIsUnicodeText){// Do standard stuff -- read ANSI in ANSIbReadData = CStdioFile::ReadString(rString);// Get the current code pageUINT nLocaleCodePage = GetCurrentLocaleCodePage();// If we got it OK...if (nLocaleCodePage > 0){// if file code page does not match the system code page, we need to do a double conversion!if (nLocaleCodePage != (UINT)m_nFileCodePage){int nStringBufferChars = rString.GetLength() + 1;pszUnicodeString= new wchar_t[nStringBufferChars]; // Initialise to something safememset(pszUnicodeString, 0, sizeof(wchar_t) * nStringBufferChars);// Convert to Unicode using the file code pagenChars = GetUnicodeStringFromMultiByteString(rString, pszUnicodeString, nStringBufferChars, m_nFileCodePage);// Convert back to multibyte using the system code page// (This doesn't really confer huge advantages except to avoid "mangling" of non-convertible special// characters. So, if a file in the E.European code page is displayed on a system using the // western European code page, special accented characters which the system cannot display will be// replaced by the default character (a hash or something), rather than being incorrectly mapped to// other, western European accented characters).if (nChars > 0){// Calculate how much we need for the MB buffer (it might be larger)nStringBufferChars = GetRequiredMultiByteLengthForUnicodeString(pszUnicodeString,nLocaleCodePage);pszMultiByteString= new char[nStringBufferChars];  nChars = GetMultiByteStringFromUnicodeString(pszUnicodeString, pszMultiByteString, nStringBufferChars, nLocaleCodePage);rString = (CString)pszMultiByteString;}}}}else{pszUnicodeString= new wchar_t[nMAX_LINE_CHARS]; // Initialise to something safememset(pszUnicodeString, 0, sizeof(wchar_t) * nMAX_LINE_CHARS);// Read as Unicode, convert to ANSI// Bug fix by Dennis Jeryd 06/07/2003: initialise bReadDatabReadData = (NULL != fgetws(pszUnicodeString, nMAX_LINE_CHARS, m_pStream));if (bReadData){// Calculate how much we need for the multibyte stringint nRequiredMBBuffer = GetRequiredMultiByteLengthForUnicodeString(pszUnicodeString,m_nFileCodePage);pszMultiByteString= new char[nRequiredMBBuffer];  nChars = GetMultiByteStringFromUnicodeString(pszUnicodeString, pszMultiByteString, nRequiredMBBuffer, m_nFileCodePage);if (nChars > 0){rString = (CString)pszMultiByteString;}}}#endif// Then remove end-of-line character if in Unicode text modeif (bReadData){// Copied from FileTxt.cpp but adapted to Unicode and then adapted for end-of-line being just '\r'. nLen = rString.GetLength();if (nLen > 1 && rString.Mid(nLen-2) == sNEWLINE){rString.GetBufferSetLength(nLen-2);}else{lpsz = rString.GetBuffer(0);if (nLen != 0 && (lpsz[nLen-1] == _T('\r') || lpsz[nLen-1] == _T('\n'))){rString.GetBufferSetLength(nLen-1);}}}}// Ensure we always delete in case of exceptioncatch(...){if (pszUnicodeString)delete [] pszUnicodeString;if (pszMultiByteString) delete [] pszMultiByteString;throw;}if (pszUnicodeString)delete [] pszUnicodeString;if (pszMultiByteString)delete [] pszMultiByteString;return bReadData;}// --------------------------------------------------------------------------------------------////CStdioFileEx::WriteString()//// --------------------------------------------------------------------------------------------// Returns:    void// Parameters: LPCTSTR lpsz//// Purpose:Writes string to file either in Unicode or multibyte, depending on whether the caller specified the//CStdioFileEx::modeWriteUnicode flag. Override of base class function.// Notes:If writing in Unicode we need to://a) Write the Byte-order-mark at the beginning of the file//b) Write all strings in byte-mode//-If we were compiled in Unicode, we need to convert Unicode to multibyte if //we want to write in multibyte//-If we were compiled in multi-byte, we need to convert multibyte to Unicode if //we want to write in Unicode.// Exceptions:None.//void CStdioFileEx::WriteString(LPCTSTR lpsz){wchar_t*pszUnicodeString= NULL; char*pszMultiByteString= NULL;try{// If writing Unicode and at the start of the file, need to write byte markif (m_nFlags & CStdioFileEx::modeWriteUnicode){// If at position 0, write byte-order mark before writing anything elseif (!m_pStream || GetPosition() == 0){wchar_t cBOM = (wchar_t)nUNICODE_BOM;CFile::Write(&cBOM, sizeof(wchar_t));}}// If compiled in Unicode...#ifdef _UNICODE// If writing Unicode, no conversion neededif (m_nFlags & CStdioFileEx::modeWriteUnicode){// Write in byte modeCFile::Write(lpsz, lstrlen(lpsz) * sizeof(wchar_t));}// Else if we don't want to write Unicode, need to convertelse{intnChars = lstrlen(lpsz);// Why plus 1? Because yes//intnBufferSize = nChars * sizeof(char);// leave space for multi-byte charsintnCharsWritten = 0;intnBufferSize = 0;pszUnicodeString= new wchar_t[nChars + 1]; ZeroMemory(pszUnicodeString,nChars + 1);// Copy string to Unicode bufferlstrcpy(pszUnicodeString, lpsz);// Work out how much space we need for the multibyte conversion //nBufferSize= GetRequiredMultiByteLengthForUnicodeString(pszUnicodeString, m_nFileCodePage);// Get multibyte string//nCharsWritten = GetMultiByteStringFromUnicodeString(pszUnicodeString,pszMultiByteString , nBufferSize, m_nFileCodePage);int u8len=::WideCharToMultiByte(CP_UTF8,NULL,pszUnicodeString,wcslen(pszUnicodeString),NULL,0,NULL,NULL);char*szU8=new char[u8len+1];ZeroMemory(szU8,u8len+1);::WideCharToMultiByte(CP_UTF8,NULL,pszUnicodeString,wcslen(pszUnicodeString),szU8,u8len,NULL,NULL);szU8[u8len]='\0';if(pszUnicodeString[0]==0xfeff){//CFile::Write(/*(const void*)*/pszUnicodeString,nChars*sizeof(wchar_t));                  CFile::Write(/*(const void*)*/szU8,u8len*sizeof(char));}else{                //CFile::Write(/*(const void*)*/pszUnicodeString,nChars*sizeof(wchar_t));  CFile::Write(/*(const void*)*/szU8,u8len*sizeof(char));}}// Else if *not* compiled in Unicode#else// If writing Unicode, need to convertif (m_nFlags & CStdioFileEx::modeWriteUnicode){intnChars = lstrlen(lpsz) + 1; // Why plus 1? Because yesintnBufferSize = nChars * sizeof(wchar_t);intnCharsWritten = 0;pszUnicodeString= new wchar_t[nChars];pszMultiByteString= new char[nChars]; // Copy string to multibyte bufferlstrcpy(pszMultiByteString, lpsz);nCharsWritten = GetUnicodeStringFromMultiByteString(pszMultiByteString, pszUnicodeString, nChars, m_nFileCodePage);if (nCharsWritten > 0){// Do byte-mode write using actual chars written (fix by Howard J Oh)//CFile::Write(pszUnicodeString, lstrlen(lpsz) * sizeof(wchar_t));CFile::Write(pszUnicodeString, nCharsWritten*sizeof(wchar_t));}else{ASSERT(false);}}// Else if we don't want to write Unicode, no conversion needed, unless the code page differselse{//// Do standard stuff//CStdioFile::WriteString(lpsz);// Get the current code pageUINT nLocaleCodePage = GetCurrentLocaleCodePage();// If we got it OK, and if file code page does not match the system code page, we need to do a double conversion!if (nLocaleCodePage > 0 && nLocaleCodePage != (UINT)m_nFileCodePage){intnChars = lstrlen(lpsz) + 1; // Why plus 1? Because yespszUnicodeString= new wchar_t[nChars]; // Initialise to something safememset(pszUnicodeString, 0, sizeof(wchar_t) * nChars);// Convert to Unicode using the locale code page (the code page we are using in memory)nChars = GetUnicodeStringFromMultiByteString((LPCSTR)(const char*)lpsz, pszUnicodeString, nChars, nLocaleCodePage);// Convert back to multibyte using the file code page// (Note that you can't reliably read a non-Unicode file written in code page A on a system using a code page B,// modify the file and write it back using code page A, unless you disable all this double-conversion code.// In effect, you have to choose between a mangled character display and mangled file writing).if (nChars > 0){// Calculate how much we need for the MB buffer (it might be larger)nChars = GetRequiredMultiByteLengthForUnicodeString(pszUnicodeString, m_nFileCodePage);pszMultiByteString= new char[nChars];  memset(pszMultiByteString, 0, sizeof(char) * nChars);nChars = GetMultiByteStringFromUnicodeString(pszUnicodeString, pszMultiByteString, nChars, m_nFileCodePage);// Do byte-mode write. This avoids annoying "interpretation" of \n's as \r\nCFile::Write((const void*)pszMultiByteString, nChars * sizeof(char));}}else{// Do byte-mode write. This avoids annoying "interpretation" of \n's as \r\nCFile::Write((const void*)lpsz, lstrlen(lpsz)*sizeof(char));}}#endif}// Ensure we always clean upcatch(...){if (pszUnicodeString)delete [] pszUnicodeString;if (pszMultiByteString)delete [] pszMultiByteString;throw;}if (pszUnicodeString)delete [] pszUnicodeString;if (pszMultiByteString)delete [] pszMultiByteString;}