The CBN_CLOSEUP notification message is sent when the list box of a combo box has been closed. The parent window of the combo box receives this notification message through the WM_COMMAND message.
CBN_CLOSEUP
idComboBox = (int) LOWORD(wParam); // identifier of combo box
hwndComboBox = (HWND) lParam; // handle of combo box
Remarks
This notification message is not sent to a combo box that has the CBS_SIMPLE style.
In general, you cannot predict the order in which notifications will be sent. In particular, a CBN_SELCHANGE notification message may occur either before or after a CBN_CLOSEUP notification message.
See Also