Webcam light still on ever after disconnecting the drivers vb.net 2008 -

i want capture image webcam , found excellent code that, problem after disconnecting webcam drivers webcam light still on. seems webcam still in use. how adjust it?

 sendmessage(hhwnd, wm_cap_driver_disconnect, deviceid, 0)         destroywindow(hhwnd) 

webcam class

public class form1     const wm_cap short = &h400s     const wm_cap_driver_connect integer = wm_cap + 10     const wm_cap_driver_disconnect integer = wm_cap + 11     const wm_cap_edit_copy integer = wm_cap + 30     public const wm_cap_get_status integer = wm_cap + 54     public const wm_cap_dlg_videoformat integer = wm_cap + 41     const wm_cap_set_preview integer = wm_cap + 50     const wm_cap_set_previewrate integer = wm_cap + 52     const wm_cap_set_scale integer = wm_cap + 53     const ws_child integer = &h40000000     const ws_visible integer = &h10000000     const swp_nomove short = &h2s     const swp_nosize short = 1     const swp_nozorder short = &h4s     const hwnd_bottom short = 1     private deviceid integer = 0 ' current device id     private hhwnd integer ' handle preview window     declare function sendmessage lib "user32" alias "sendmessagea" _         (byval hwnd integer, byval wmsg integer, byval wparam integer, _         byref lparam capstatus) boolean     declare function sendmessage lib "user32" alias "sendmessagea" _        (byval hwnd integer, byval wmsg integer, byval wparam boolean, _        byref lparam integer) boolean     declare function sendmessage lib "user32" alias "sendmessagea" _          (byval hwnd integer, byval wmsg integer, byval wparam integer, _          byref lparam integer) boolean     declare function setwindowpos lib "user32" alias "setwindowpos" (byval hwnd integer, _         byval hwndinsertafter integer, byval x integer, byval y integer, _         byval cx integer, byval cy integer, byval wflags integer) integer      declare function destroywindow lib "user32" (byval hndw integer) boolean     structure pointapi         dim x integer         dim y integer     end structure         private sub loaddevicelist()         dim strname string = space(100)         dim strver string = space(100)         dim breturn boolean         dim x short = 0         '          ' load name of avialable devices lstdevices         '                     '             '   driver name , version             '             breturn = capgetdriverdescriptiona(x, strname, 100, strver, 100)             '             ' if there device add device name list             '             if breturn lstdevices.items.add(strname.trim)             x += ctype(1, short)         loop until breturn = false     end sub      private sub openpreviewwindow()         ' connect device         '      sendmessage(hhwnd, wm_cap_driver_connect, deviceid, 0)         end sub       private sub form1_load(byval sender system.object, byval e system.eventargs) handles mybase.load         loaddevicelist()              end sub       private sub closepreviewwindow()         '         ' disconnect device         '         sendmessage(hhwnd, wm_cap_driver_disconnect, deviceid, 0)         destroywindow(hhwnd)     end sub 

start , stop camera

    private sub btnstart_click(byval sender system.object, byval e system.eventargs) handles btnstart.click         deviceid = lstdevices.selectedindex         openpreviewwindow()         dim breturn boolean         dim s capstatus         breturn = sendmessage(hhwnd, wm_cap_get_status, marshal.sizeof(s), s)     end sub             private sub btnstop_click(byval sender system.object, byval e system.eventargs) handles btnstop.click         closepreviewwindow()           sendmessage(hhwnd, wm_cap_driver_disconnect, deviceid, 0)     end sub         end class