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CFile::GetLength

Obtains the current logical length of the file in bytes.

virtual ULONGLONG GetLength( ) const;

Return Value

The length of the file.

Example

CFile* pFile = NULL;
// Constructing a CFile object with this override may throw 
// a CFile exception, and won't throw any other exceptions. 
// Calling CString::Format() may throw a CMemoryException, 
// so we have a catch block for such exceptions, too. Any 
// other exception types this function throws will be 
// routed to the calling function. 
try
{
   pFile = new CFile(_T("C:\\WINDOWS\\SYSTEM.INI"),
      CFile::modeRead | CFile::shareDenyNone);
   ULONGLONG dwLength = pFile->GetLength();
   CString str;
   str.Format(_T("Your SYSTEM.INI file is %I64u bytes long."), dwLength);
   AfxMessageBox(str);
}
catch (CFileException* pEx)
{
   // Simply show an error message to the user.
   pEx->ReportError();
   pEx->Delete();
}
catch(CMemoryException* pEx)
{
   pEx->ReportError();
   pEx->Delete();
   // We can't recover from this memory exception, so we'll 
   // just terminate the app without any cleanup. Normally, 
   // an application should do everything it possibly can to 
   // clean up properly and _not_ call AfxAbort().
   AfxAbort();
}

// If an exception occurs in the CFile constructor, 
// the language will free the memory allocated by new 
// and will not complete the assignment to pFile. 
// Thus, our clean-up code needs to test for NULL. 
if (pFile != NULL)
{
   pFile->Close();
   delete pFile;
}         

Requirements

Header: afx.h

See Also

Reference

CFile Class

Hierarchy Chart

CFile::SetLength