Re: Exception in CFileDialog - why?
Creation of CFileDialog is very inexpensive operation. You don't gain
anything by reusing it. DoModal itself is much more expensive.
"Vanja" <Vanja@discussions.microsoft.com> wrote in message
news:BEF69A5E-CD82-46DB-A62B-9154164791CD@microsoft.com...
Hello,
Does someone know why the CFileDialog throws CInvalidArgException if
"recycled" (DoModal called the second time)? The problem happens only on
Vista und Windows 7, and only if using bVistaSyle==TRUE. Creating the
dialog
with bVistaStyle==FALSE solves the problem, but it's a poor solution.
Also,
if file filters are not used, no exception occurs.
Here's the code (more or less the same example like in MSDN):
// szFilters is a text string that includes two file name filters:
// "*.my" for "MyType Files" and "*.*' for "All Files."
TCHAR szFilters[]= _T("MyType Files (*.my)|*.my|All Files (*.*)|*.*||");
// Create an Open dialog; the default file name extension is ".my".
CFileDialog fileDlg(TRUE, _T("my"), _T("*.my"),
OFN_FILEMUSTEXIST | OFN_HIDEREADONLY, szFilters, NULL, 0,
/*bVistaStyle*/ TRUE);
// first time -> ok
fileDlg.DoModal();
// second time -> not so ok (CInvalidArgException thrown)
// If the dialog was created with szFilters==NULL, no problems.
// If the dialog was created with bVistaStyle==FALSE, no problems.
fileDlg.DoModal();
Stack at the point of exception (first-chance) is:
mfc90ud.dll!AfxThrowInvalidArgException() Line 233
mfc90ud.dll!CFileDialog::ApplyOFNToShellDialog() Line 388
mfc90ud.dll!CFileDialog::DoModal() Line 706
CommonDialog_Test.exe!CCommonDialog_TestDlg::OnBnClickedBtnOpentwice()
Line 142
. . . .
I could easily circumvent the problem by always creating a fresh instance
of
CFileDialog. But since the file-browser is required many times in my
application, my intention was to create it once, re-use it and thus
improve
the reaction time.
Thanks in advance.
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it, not this year but later..."
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