CFileDialog::GetIFileOpenDialog
Retrieves a pointer to the internal COM object for a given CFileDialog.
IFileOpenDialog* GetIFileOpenDialog();
Use this function only under Windows Vista with an object that has bVistaStyle set to true. This function returns NULL if the CFileDialog is not an Open dialog box or if bVistaStyle is set to false. In this final case, the function only returns NULL in release mode - in debug mode it will throw an assertion.
For more information about the IFileOpenDialog interface, see IFileOpenDialog.