This code specifies that the list box of a combo box will be dropped down. It is sent just before the combo-box list box is made visible. The control's parent window receives this code through a WM_COMMAND message from the control.
Parameter |
Description |
wParam |
Specifies the control ID of the combo box. |
|
lParam |
Contains the combo-box window handle in its low-order word and the CBN_DROPDOWN code in the high-order word. |
This message does not occur if the combo box does not contain a drop-down list box.