An application sends an LB_GETSELCOUNT message to retrieve the total number of selected items in a multiple-selection list box.
LB_GETSELCOUNT
wParam = 0; // not used; must be zero
lParam = 0; // not used; must be zero
This message has no parameters.
The return value is the count of selected items in the list box. If the list box is a single-selection list box, the return value is LB_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.
List Boxes Overview, List Box Messages, LB_SETSEL