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4/8/2010

This message is sent when the list box of a combo box is about to be made visible. The parent window of the combo box receives this message through the WM_COMMANDmessage.

Syntax 

CBN_DROPDOWN 
idComboBox = (int)LOWORD(
wParam); 

hwndComboBox = (HWND) 
lParam;

Parameters

idComboBox

Identifier of the combo box.

hwndComboBox

Handle to the combo box.

Return Value

None.

Remarks

This message can occur only for a combo box with the CBS_DROPDOWN or CBS_DROPDOWNLIST style.

Requirements

Header winuser.h
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also