The CDN_SELCHANGE notification message is sent by an Explorer-style Open or Save As common dialog box when the selection changes in the list box that displays the contents of the currently opened folder or directory. Your OFNHookProc hook procedure receives this message in the form of a WM_NOTIFY message.
CDN_SELCHANGE
lpon = (LPOFNOTIFY) lParam;
The OFNOTIFY structure contains an NMHDR structure whose code member indicates the CDN_SELCHANGE notification code.
The return value is ignored.
The system sends this notification only if the dialog box was created using the OFN_EXPLORER value.
To get the name of the newly selected file or folder, the hook procedure can send the CDM_GETFILEPATH or CDM_GETSPEC message to the common dialog box.
Windows NT: Requires version 4.0 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in commdlg.h.
Common Dialog Box Library Overview, Common Dialog Box Messages, CDM_GETFILEPATH, CDM_GETSPEC, GetOpenFileName, GetSaveFileName, NMHDR, OFNHookProc, OFNOTIFY, WM_NOTIFY