自学教程：C++ IsEOF函数代码示例

void CXML_Parser::SkipLiterals(const CFX_ByteStringC& str) {  m_nOffset = m_nBufferOffset + (FX_FILESIZE)m_dwIndex;  if (IsEOF()) {    return;  }  int32_t i = 0, iLen = str.GetLength();  do {    while (m_dwIndex < m_dwBufferSize) {      if (str.GetAt(i) != m_pBuffer[m_dwIndex++]) {        i = 0;      } else {        i++;        if (i == iLen) {          break;        }      }    }    m_nOffset = m_nBufferOffset + (FX_FILESIZE)m_dwIndex;    if (i == iLen) {      return;    }    if (m_dwIndex < m_dwBufferSize || IsEOF()) {      break;    }  } while (ReadNextBlock());  while (!m_pDataAcc->IsEOF()) {    ReadNextBlock();    m_nOffset = m_nBufferOffset + (FX_FILESIZE)m_dwBufferSize;  }  m_dwIndex = m_dwBufferSize;}

bool Tokenizer::SkipToEOL(bool nestBraces, bool skippingComment){    // skip everything until we find EOL    while (1)    {        while (NotEOF() && CurrentChar() != '/n')        {            if (CurrentChar() == '/' && NextChar() == '*')            {                SkipComment(false); // don't skip whitespace after the comment                if (skippingComment && CurrentChar() == '/n')                {                    continue; // early exit from the loop                }            }            if (nestBraces && CurrentChar() == _T('{'))                ++m_NestLevel;            else if (nestBraces && CurrentChar() == _T('}'))                --m_NestLevel;            MoveToNextChar();        }        wxChar last = PreviousChar();        // if DOS line endings, we 've hit /r and we skip to /n...        if (last == '/r')            last = m_Buffer.GetChar(m_TokenIndex - 2);        if (IsEOF() || last != '//')            break;        else            MoveToNextChar();    }    if (IsEOF())        return false;    return true;}

bool TextCutter::SkipWhiteSpace(){    if (IsEOF())        return false;    while (!IsEOF() && isspace(CurrentChar()))        MoveToNextChar();    return true;}

void CollateRecordset::MoveNext(){    if (!IsEOF())    {	++m_index;	if (m_index == m_items.size() && !IsEOF())	    GetSome();    }}

BOOL CSourceODBC::stdFillTable1(CString field1, CString& strValue1, CString field2, long& lngValue2){    if ( IsEOF() ) return FALSE;    strValue1 = m_database.GetColomn(CString(field1))->GetValueAsString();    lngValue2 = m_database.GetColomn(CString(field2))->GetValueAsLong();    MoveNext();    if ( IsEOF() ) return FALSE;    return TRUE;}

void CSessions::clearRecords(){	if (!IsBOF() || !IsEOF())	{		while (!IsEOF())		{			Delete();			MoveNext();		}	}}

void CXML_Parser::GetTagName(CFX_ByteString &space, CFX_ByteString &name, FX_BOOL &bEndTag, FX_BOOL bStartTag){    m_nOffset = m_nBufferOffset + (FX_FILESIZE)m_dwIndex;    if (IsEOF()) {        return;    }    bEndTag = FALSE;    FX_BYTE ch;    FX_INT32 iState = bStartTag ? 1 : 0;    do {        while (m_dwIndex < m_dwBufferSize) {            ch = m_pBuffer[m_dwIndex];            switch (iState) {                case 0:                    m_dwIndex ++;                    if (ch != '<') {                        break;                    }                    iState = 1;                    break;                case 1:                    if (ch == '?') {                        m_dwIndex ++;                        SkipLiterals(FX_BSTRC("?>"));                        iState = 0;                        break;                    } else if (ch == '!') {                        m_dwIndex ++;                        SkipLiterals(FX_BSTRC("-->"));                        iState = 0;                        break;                    }                    if (ch == '/') {                        m_dwIndex ++;                        GetName(space, name);                        bEndTag = TRUE;                    } else {                        GetName(space, name);                        bEndTag = FALSE;                    }                    return;            }        }        m_nOffset = m_nBufferOffset + (FX_FILESIZE)m_dwIndex;        if (m_dwIndex < m_dwBufferSize || IsEOF()) {            break;        }    } while (ReadNextBlock());}

   double   PGRecordset::GetDoubleValue(const AnsiString &FieldName) const   //---------------------------------------------------------------------------()   // DESCRIPTION:   // Returns the value of a string in the current row in the recordset.   //---------------------------------------------------------------------------()   {      if (IsEOF())      {         ReportEOFError_(FieldName);         return 0;      }      try      {         int iColIdx = GetColumnIndex_(FieldName);         char *pValue = PQgetvalue(result_, cur_row_num_, iColIdx);         double dbVal = pValue ? atof(pValue) : 0;         return dbVal;      }      catch (...)      {         ErrorManager::Instance()->ReportError(ErrorManager::Medium, 5091, "PGRecordset::GetDoubleValue", "An unknown error occurred while reading value from recordset: " + FieldName);         throw;      }   }

void SearchRecordset::SelectThisItem(){    if (IsEOF())	return;    mediadb::didl::MetadataList::const_iterator ci = m_items.begin();    for (unsigned int i=0; i<m_index; ++i)	++ci;    std::string objectid;    for (mediadb::didl::Metadata::const_iterator i = ci->begin();	 i != ci->end();	 ++i)	if (i->tag == "id")	{	    objectid = i->content;	    break;	}    m_freers = db::FreeRecordset::Create();    mediadb::didl::ToRecord(*ci, m_freers);    m_id = m_parent->IdForObjectId(objectid);    m_got_what = GOT_BASIC;}

BOOL CSqlite3Recordset::GetField(short iIndex, LPTSTR pData, UINT cchMax){   _ASSERTE(IsOpen());   _ASSERTE(iIndex>=0 && iIndex<m_nCols);   if( IsEOF() ) return FALSE;   if( iIndex < 0 || iIndex >= m_nCols ) return FALSE;   if( m_lType == DB_OPEN_TYPE_FORWARD_ONLY ) {#if !defined(UNICODE)      USES_CONVERSION;      _tcsncpy(pData, A2T( (char*)::sqlite3_column_text(m_pVm, iIndex) ), cchMax);#else  // UNICODE      _tcsncpy(pData, (WCHAR*) ::sqlite3_column_text16(m_pVm, iIndex), cchMax);#endif // UNICODE   }   else {      LPSTR pstr = m_ppSnapshot[ ((m_iPos + 1) * m_nCols) + iIndex ];      if( pstr == NULL ) {         _tcscpy(pData, _T(""));      }      else {         USES_CONVERSION;         LPCSTR pstr = m_ppSnapshot[ ((m_iPos + 1) * m_nCols) + iIndex ];         _tcsncpy(pData, A2CT(pstr), cchMax);      }   }   return TRUE;}

wchar_t EasyUnicodeFileLE::readWchar( )//读取一个宽字符{	if( !IsReadMode ) return L'';//输出模式不允许读入	if( IsEOF( ) ) return L'';//如果已经在文件尾了，就不读了	wchar_t Temp2[ 2 ];	wchar_t tempWC[ 2 ];	try {		F.read( (char *)tempWC, 2 );		tempWC[ 1 ] = L'/0';		if( tempWC[ 0 ] == L'/x000D' ) {			F.read( (char *)Temp2, 2 );			Temp2[ 1 ] = L'/0';			if( Temp2[ 0 ] == L'/x000A' ) return L'/n';			else {				SetPointer( -1, ios_base::cur );				return tempWC[ 0 ];			}		}		else return tempWC[ 0 ];	}	catch( ... ) {		cout << "ERROR_EUFLE008 - Unknown error." << endl;		system( "PAUSE" );		return L'';	}	return tempWC[ 0 ];}

   bool    PGRecordset::GetIsNull(const AnsiString &FieldName) const   //---------------------------------------------------------------------------()   // DESCRIPTION:   // Returns true if the column contains NULL   //---------------------------------------------------------------------------()   {      if (IsEOF())      {         ReportEOFError_(FieldName);         return false;      }      try      {         int iColIdx = GetColumnIndex_(FieldName);         bool isNull = PQgetisnull(result_, cur_row_num_, iColIdx) == 1;         return isNull;      }      catch (...)      {         ErrorManager::Instance()->ReportError(ErrorManager::High, 5301, "PGRecordset::GetIsNull", "An error occured while checking for null.");         throw;      }   }

      /// <summary>Reads the next line, if any</summary>      /// <param name="line">The line.</param>      /// <returns>True if read, false if EOF</returns>      /// <exception cref="Logic::InvalidOperationException">Stream has been closed (reader has been move-copied)</exception>      /// <exception cref="Logic::IOException">An I/O error occurred</exception>      bool  StringReader::ReadLine(wstring&  line)      {         DWORD start = Position,    // Start of line               end   = Length;      // End of characters on line         WCHAR ch;         // EOF: Return false         if (IsEOF())         {            line.clear();            return false;         }         // Search for EOF/CRLF/CR         while (ReadChar(ch))         {            // CR/LF/CRLF: Set of chars marker,             if (ch == '/r' || ch == '/n')            {               // Mark end-of-text               end = Position-1;               // Consume entire CRLF if present               if (ch == '/r' && PeekChar(ch) && ch == '/n')                  ReadChar(ch);               // Position marker now at start of new line, end-of-char marker at last character               break;            }         }         // Return line text without CRLF         line = wstring(Buffer.get() + start, Buffer.get() + end);         return true;      }

/*=========================================================================== * * Class CSrFile Method - bool ReadLine (Buffer); * * Inputs a line of text from a text file. * *=========================================================================*/bool CSrFile::ReadLine (CSString& Buffer) {  byte    Value;  size_t  Result;  //SSCHAR  TempBuffer[256];  //SSCHAR* pResult;	/* Set some initial string size */  Buffer.SetSizeEmpty(64);  //Buffer.Empty();  while (!IsEOF()) {      		/* Attempt to input buffer */    Result = fread(&Value, 1, 1, m_pFile);    if (Result != 1) {      if (HasError()) return AddSrSystemError("Failed to read byte from file!");      return (true);    }    if (Value == '/n') {      ++m_LineCount;      return (true);     }    else {      Buffer += Value;     }   }  return (true);}

      /// <summary>Reads the next character</summary>      /// <param name="c">Next character</param>      /// <returns>True if read, false if EOF</returns>      /// <exception cref="Logic::InvalidOperationException">Stream has been closed (reader has been move-copied)</exception>      /// <exception cref="Logic::IOException">An I/O error occurred</exception>      bool  StringReader::ReadChar(WCHAR&  c)      {         // Ensure stream has not been moved         if (Input == nullptr)            throw InvalidOperationException(HERE, L"Underlying stream has been closed");         // First Call: Read entire file          else if (Buffer == nullptr)            Buffer = FileStream::ConvertFileBuffer(Input, Length);         // EOF: Return false         if (IsEOF())         {            c = NULL;            return false;         }         // Increment line number          if (c == L'/n')            LineNum++;         // Set byte, advance position, return true         c = Buffer.get()[Position++];         return true;      }

 bool Loop() {    size_t row = 0;    if (!(IsBOF() && IsEOF())) for (MoveFirst(); !IsEOF(); MoveNext(), row++)    {       //TRACE(_T("row %3d/n"), row);       NewRecord();       for (int i = 0; i < GetFieldCount(); i++)       {          COleVariant var;    	   GetFieldValue(i, var);          SaveField(i, var);       }       SaveRecord();    }    return true; }

bool Tokenizer::SkipUnwanted(){    while (SkipWhiteSpace() || SkipComment())        ;    wxChar c = CurrentChar();    const unsigned int startIndex = m_TokenIndex;    if (c == _T('#'))    {        const PreprocessorType type = GetPreprocessorType();        if (type != ptOthers)        {            HandleConditionPreprocessor(type);            c = CurrentChar();        }    }    // skip [XXX][YYY]    if (m_State & tsSkipSubScrip)    {        while (c == _T('[') )        {            SkipBlock('[');            SkipWhiteSpace();            if (IsEOF())                return false;            c = CurrentChar();        }    }    // skip the following = or ?    if (m_State & tsSkipEqual)    {        if (c == _T('='))        {            if (!SkipToOneOfChars(_T(",;}"), true, true, false))                return false;        }    }    else if (m_State & tsSkipQuestion)    {        if (c == _T('?'))        {            if (!SkipToOneOfChars(_T(";}"), false, true))                return false;        }    }    // skip the following white space and comments    while (SkipWhiteSpace() || SkipComment())        ;    if (startIndex != m_TokenIndex && CurrentChar() == _T('#'))        return SkipUnwanted();    return NotEOF();}

bool TextCutter::MoveToNextChar(){    if (IsEOF())        return false;	++m_CurIdx;	++m_CurColumn;    AdjustColumn();    return true;}

void EasyUnicodeFileLE::SetPointer( std::streamoff off, basic_istream< char, char_traits< char > >::pos_type PosType ){	/*	参数说明：		off ：需要偏移的值		PosType ：搜索的起始位置	枚举类型：		enum seek_dir {beg, cur, end};		每个枚举常量的含义：		ios::beg ：文件流的起始位置		ios::cur ：文件流的当前位置		ios::end ：文件流的结束位置	*/	//注意文件头	if( IsEOF( ) ) F.clear( );	if( (int)PosType == ios_base::beg && off >= 0 ) {		F.seekg( 2 /*+ 2 * off*/, ios_base::beg );//FF FE		for( int i = 0; i < off; i ++ ) readWchar( );	}	else if( (int)PosType == ios_base::cur ) {		F.seekg( 0/*2 * off*/, ios_base::cur );		if( off >= 0 ) for( int i = 0; i < off; i ++ ) readWchar( );		else for( int i = 0; i < -off; i ++ ) {			try {				F.seekg( -4, ios_base::cur );				if( readWchar( ) == L'/n' ) {					F.seekg( -4, ios_base::cur );					continue;				}			}			catch( ... ) {				cout << "ERROR_EUFLE010 - Unknown error." << endl;				system( "PAUSE" );			}		}	}	else if( (int)PosType == ios_base::end && off <= 0 ) {		F.seekg( 0/*2 * off*/, ios_base::end );		for( int i = 0; i < -off; i ++ ) {			try {				F.seekg( -4, ios_base::cur );			   	if( readWchar( ) == L'/n' ) {					F.seekg( -4, ios_base::cur );					continue;				}			}			catch( ... ) {				cout << "ERROR_EUFLE011 - Unknown error." << endl;				system( "PAUSE" );   			}		}	}	else cout << "ERROR_EUFLE012 - Unsupport referring file mode." << endl;	return;}

void CXML_Parser::GetAttrValue(CFX_WideString &value){    m_nOffset = m_nBufferOffset + (FX_FILESIZE)m_dwIndex;    if (IsEOF()) {        return;    }    CFX_UTF8Decoder decoder;    uint8_t mark = 0, ch = 0;    do {        while (m_dwIndex < m_dwBufferSize) {            ch = m_pBuffer[m_dwIndex];            if (mark == 0) {                if (ch != '/'' && ch != '"') {                    return;                }                mark = ch;                m_dwIndex ++;                ch = 0;                continue;            }            m_dwIndex ++;            if (ch == mark) {                break;            }            if (ch == '&') {                decoder.AppendChar(GetCharRef());                if (IsEOF()) {                    value = decoder.GetResult();                    return;                }            } else {                decoder.Input(ch);            }        }        m_nOffset = m_nBufferOffset + (FX_FILESIZE)m_dwIndex;        if (ch == mark || m_dwIndex < m_dwBufferSize || IsEOF()) {            break;        }    } while (ReadNextBlock());    value = decoder.GetResult();}