Re: How to select a lot of files

"Tom Serface" <>
Thu, 19 Jun 2008 22:26:26 -0700
Glad you got it working Drew. For the future you may be interested in this
class from CodeJock.

It has a "filter" option that allows you to set any file types that you want
to display in any folders. It also allows you to drag and drop files or
folders onto your UI.

If what you have is good for selecting the number of files you need than
that's cool of course. I've just been where you are before and then I had
someone want to select 100K files :o)


"Drew" <> wrote in message

Thanks Giovanni that got me going. I should have RTFM better (or not as
docs suggest I could use GetStartPosition()/GetNextPathName() which
work, as I found out).

Thanks also for the suggestion Tom but need to limit the scope of file
that are handled and Giovanni's code got me going in the right direction.

Thanks again,

"Giovanni Dicanio" <> wrote in message

"Drew" <> ha scritto nel messaggio

I'm using OFN_ALLOWMULTISELECT as a CFileDialog style and I am having
problem that when I select above a certain number of files my DoModal()
call returns IDCANCEL.


I found an old post I wrote in this newsgroup, with a sample code that
interest you:

[subject] CFileDialog failure
[date] 2007, October 19th


// Given the file list from Open file dialog in multi-select mode,
// parses it and prints its content to the user.
void CTestDlg::ProcessFileList( LPCTSTR fileList )
   ASSERT( fileList != NULL );

   // Parse file list from CFileDialog,
   // and build a string list from it
   LPCTSTR pstr = fileList;
   std::vector< CString > strings;
   while ( true )
       if ( *pstr == _T('\0') && *(pstr+1) == _T('\0') )

       // Ciao 0
       // 1234 5
       // *
       // 0123 4
       strings.push_back( CString(pstr) );
       pstr += (_tcslen(pstr) + 1);

   // Build a message with the file names
   CString msg;
   msg = _T("*** Selected files ***\n\n");
   msg += _T("Path : ") +; // First string is path name
   msg += _T("\n\n");
   for ( size_t i = 1; i < strings.size(); i++ )
       msg +=;
       msg += _T("\n");
   AfxMessageBox( msg );


// Tests Open file dialog in multi-select mode.
void CTestDlg::OnBnClickedButton1()
   // Max files in list (including folder path)
   const int MaxFileCount = 50;

   // Max TCHARs per file
   const int MaxFilePath = MAX_PATH;

   // Calculate approx size for the given number of max files.
   // The "+1" is for the terminating NUL (_T('\0')) character.
   const int MaxFileBuffer = MaxFileCount * MaxFilePath + 1;
// const int MaxFileBuffer = 30; // TEST for small buffer

   // Buffer for file names
   std::vector< TCHAR > fileNamesBuffer(MaxFileBuffer);

   // File dialog object, dynamically allocated
   // at each loop iteration
   CFileDialog * fileDlg = NULL;
   while ( true )
       // Allocate a new file dialog object
       ASSERT( fileDlg == NULL );
       fileDlg = new CFileDialog(
           TRUE, // Open file dialog
           NULL, // No default extension
           NULL, // Initial file name
           _T("All files (*.*)|*.*||"), // Filter
           this // Parent

       // Hook our buffer to file dialog structure
       fileDlg->GetOFN().lpstrFile = &(fileNamesBuffer[0]);
       fileDlg->GetOFN().nMaxFile = (DWORD) fileNamesBuffer.size();

       // Clear buffer content, so we don't see garbage
       // from the previous iteration
       // (if the previous iteration failed).
       ::ZeroMemory( &(fileNamesBuffer[0]),
           fileNamesBuffer.size() * sizeof(TCHAR) );

       // Run the dialog-box
       INT_PTR result = fileDlg->DoModal();

       // Avoid memory leaks
       delete fileDlg;
       fileDlg = NULL;

       // Check result
       if ( result == IDCANCEL )
           // Failure or user pressed Cancel?
           DWORD dw = ::CommDlgExtendedError();
           if ( dw & FNERR_BUFFERTOOSMALL )
               // Failure due to few buffer memory;
               // tell that to the user
               AfxMessageBox( _T("Too many files selected.") );

               // Do another iteration

           // User pressed cancel, or other error.
           // Quit loop.

       // User pressed OK:
       // Show selected files and quit loop.
       ProcessFileList( &(fileNamesBuffer[0]) );




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