This example responds to an item in the list box being selected (LN_SELECT, WM_CONTROL message) by deleting the selected item using WinDeleteLboxItem.

#define INCL_WINWINDOWMGR       /* Window Manager Functions     */
#define INCL_WINLISTBOXES       /* Window List Box definitions  */
#include <os2.h>

LONG    lIndex;         /* selected item index                  */
LONG    lLeft;          /* items left after delete              */
HWND    hwndLbox;       /* list box window handle               */
MPARAM  mpParam1;       /* Parameter 1 (rectl structure)        */
MPARAM  mpParam2;       /* Parameter 2 (frame boolean)          */

case WM_CONTROL:
     /* switch on control code */
     switch(SHORT2FROMMP(mpParam1))
        {
        case LN_SELECT:
             hwndLbox = HWNDFROMMP(mpParam2);

             /* query index of selected item */
             lIndex = WinQueryLboxSelectedItem(hwndLbox);

             /* delete selected listbox item */
             lLeft = WinDeleteLboxItem(hwndLbox, lIndex);
             break;
        }