An application sends a CB_GETITEMHEIGHT message to determine the height of list items or the selection field in a combo box.
CB_GETITEMHEIGHT
wParam = (WPARAM) index; // item index
lParam = 0; // not used; must be zero
This parameter must be –1 to retrieve the height of the selection field. It must be zero to retrieve the height of list items, unless the combo box has the CBS_OWNERDRAWVARIABLE style. In that case, the index parameter is the zero-based index of a specific list item.
The return value is the height, in pixels, of the list items in a combo box. If the combo box has the CBS_OWNERDRAWVARIABLE style, it is is the height of the item specified by the index parameter. If index is –1, the return value is the height of the edit control (or static-text) portion of the combo box. If an error occurs, the return value is CB_ERR.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.
Combo Boxes Overview, Combo Box Messages, CB_SETITEMHEIGHT, WM_MEASUREITEM