select multiple files in CFileDialog - mfc

Question

In VC++ 6.0, MFC I want to select a multiple files
CFileDialog opendialog(true); // opens the dialog for open;
opendialog.m_ofn.lpstrTitle="SELECT FILE"; //selects the file title;
opendialog.m_ofn.lpstrFilter="text files (*.txt)\0*.txt\0"; //selects the filter;
if(opendialog.DoModal()==IDOK) //checks wether ok or cancel button is pressed;
{
srcfilename=opendialog.GetPathName(); //gets the path name;
...
}
The code sample above allows only a single file being selected at a time, but I want to select multiple text files, for example by holding down control key (ctrl+select the multiple files). How can I achieve this?

Answer 1

So in the constructor for CFileDialog you can set the dwFlags parameter to have 'OFN_ALLOWMULTISELECT'. Thats the easy part, to actually get the multiple file names back you have to modify the m_ofn.lpstrFile member in the CFileDialog to point to a buffer that you have allocated. Have a look here:
http://msdn.microsoft.com/en-us/library/wh5hz49d(VS.80).aspx
Here is an example use of it, hope the comments suffice:
void CMainFrame::OnFileOpen()
{
char strFilter[] = { "Rule Profile (*.txt)|*.txt*||" };
CFileDialog FileDlg(TRUE, "txt", NULL, OFN_ALLOWMULTISELECT, strFilter);
CString str;
int nMaxFiles = 256;
int nBufferSz = nMaxFiles*256 + 1;
FileDlg.GetOFN().lpstrFile = str.GetBuffer(nBufferSz);
if( FileDlg.DoModal() == IDOK )
{
// The resulting string should contain first the file path:
int pos = str.Find(' ', 0);
if ( pos == -1 );
//error here
CString FilePath = str.Left(pos);
// Each file name is seperated by a space (old style dialog), by a NULL character (explorer dialog)
while ( (pos = str.Find(' ', pos)) != -1 )
{ // Do stuff with strings
}
}
else
return;
}

Answer 2

An example:
CString sFilter = _T("XXX Files (*.xxx)|*.xxx|All Files (*.*)|*.*||");
CFileDialog my_file_dialog(TRUE, _T("xxx"),NULL,
OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT | OFN_FILEMUSTEXIST | OFN_ALLOWMULTISELECT,
sFilter, this);
if ( my_file_dialog.DoModal()!=IDOK )
return;
POSITION pos ( my_file_dialog.GetStartPosition() );
while( pos )
{
CString filename= my_file_dialog.GetNextPathName(pos);
//do something with the filename variable
}

Answer 3

You should pass the OFN_ALLOWMULTISELECT flag in OpenFileName structure to allow the multi selection.

Answer 4

Insert this line:
opendialog.m_ofn.Flags |= OFN_ALLOWMULTISELECT;
Or set the flag in the CFileDialog constructor as DeusAduro did.