CFile

Win32++

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CFile Class

Description

This class manages the reading from and writing to files.

CFile Members

Initialisation and Assignment

CFile

CFile();

CFile(HANDLE hFile);

CFile(LPCTSTR pszFileName, UINT nOpenFlags);

Constructor for CFile.

Attributes GetFileName

virtual const CString& GetFileName() const;

Returns the filename of the file associated with this object. GetFilePath

virtual const CString& GetFilePath() const;

Returns the full filename including the directory of the file associated with this object. GetFileTitle

virtual const CString& GetFileTitle() const;

Returns the filename of the file associated with this object, excluding the path and the file extension. GetHandle

HANDLE GetHandle() const;

Converts the CFile to a HANDLE. GetPosition

virtual ULONGLONG GetPosition() const;

Returns the current value of the file pointer, which can be used in subsequent calls to Seek. operator HANDLE

operator HANDLE() const;

Converts the CFile to a HANDLE. Operations Close

virtual BOOL Close();

Closes the file associated with this object. Closed file can no longer be read or written to.. Flush

virtual BOOL Flush();

Causes any remaining data in the file buffer to be written to the file. LockRange

virtual BOOL LockRange(ULONGLONG Pos, ULONGLONG Count);

Locks a range of bytes in and open file. Open

virtual int CollateNoCase(LPCTSTR pszText) const;

Prepares a file to be written to or read from. OpenFileDialog

virtual CString OpenFileDialog(LPCTSTR pszFilePathName = NULL,
   DWORD dwFlags = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT, LPCTSTR pszTitle = NULL, 
   LPCTSTR pszFilter = NULL, CWnd* pOwnerWnd = NULL);

Displays the file open dialog. Returns a CString containing either the selected file name or an empty CString. Read

virtual UINT Read(void* pBuf, UINT nCount);

Reads from the file, storing the contents in the specified buffer. Remove

static BOOL Remove(LPCTSTR pszFileName);

Deletes the specified file. Rename

static BOOL Rename(LPCTSTR pszOldName, LPCTSTR pszNewName);

Renames the specified file. SaveFileDialog

virtual CString SaveFileDialog(LPCTSTR pszFilePathName = NULL,
   DWORD dwFlags = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT, LPCTSTR pszTitle = NULL,
   LPCSTR pszFilter = NULL, LPCTSTR pszDefExt = NULL, CWnd* pOwnerWnd = NULL);

Displays the SaveFileDialog. Returns a CString containing either the selected file name or an empty CString. Seek

virtual ULONGLONG Seek(LONGLONG lOff, UINT nFrom);

Positions the current file pointer. Permitted values for nFrom are: FILE_BEGIN, FILE_CURRENT, or FILE_END. SeekToBegin

virtual void SeekToBegin();

Sets the current file pointer to the beginning of the file. SeekToEnd

virtual ULONGLONG SeekToEnd();

Sets the current file pointer to the end of the file. SetFilePath

virtual void SetFilePath(LPCTSTR pszNewName);

Specifies the full file name, including its path SetLength

virtual BOOL SetLength(ULONGLONG NewLen);

Changes the length of the file to the specified value. UnlockRange

virtual BOOL UnlockRange(ULONGLONG Pos, ULONGLONG Count);

Unlocks a range of bytes in an open file. Write

virtual BOOL Write(const void* pBuf, UINT nCount);

Writes the specified buffer to the file.

Remarks

The following code demonstrates how to use OpenDileDialog to retrieve the name of the file to open.

void CMainFrame::OnFileOpen()
{
  CFile File;
  CString str = File.OpenFileDialog(0, OFN_FILEMUSTEXIST, _T("Scribble Files (*.dat)\0*.dat\0\0"), this);

  if (!str.IsEmpty())
  {
    // Retrieve the PlotPoint data
    m_View.FileOpen(str);
  }
}

The following code demonstrates how to open a file for reading, and read its contents.

BOOL CView::FileOpen(LPCTSTR szFilename)
{
  DWORD nBytesRead;
  BOOL bResult = FALSE;

  // Create a handle to the file
  CFile File;
  if (File.Open(szFilename, OPEN_EXISTING))
  {
    do
    {
      nBytesRead = 0;
      PlotPoint pp;

      nBytesRead = File.Read(&pp;, sizeof(PlotPoint));
      if (nBytesRead == sizeof(PlotPoint))
        m_points.push_back(pp);
        
    } while (nBytesRead == sizeof(PlotPoint));
  }
}

Summary Information

Header file	file.h
Win32/64 support	Yes
WinCE support	Yes

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