Is there a way to intercept the "X" (close) button...

[Mel Bishop]

...so I can do some cleanup before the program actually ends?
Thanks.


------------------

[Mike Doty]

#DIM ALL
#INCLUDE "win32api.inc"
'
DECLARE FUNCTION ConsoleHandler(BYVAL dwEvent AS DWORD) AS LONG
FUNCTION PBMAIN () AS LONG
  SetConsoleCtrlHandler CODEPTR(ConsoleHandler), 1
  WAITKEY$
  SetConsoleCtrlHandler CODEPTR(ConsoleHandler), 0
END FUNCTION
'
FUNCTION ConsoleHandler(BYVAL dwEvent AS DWORD) AS LONG
  BEEP
  'Alt + F4 not trapped here, Ctrl-C not working either
  SELECT CASE dwEvent
    CASE %CTRL_C_EVENT
      PRINT "Ctrl-C pressed.  Never got this to work."
    CASE %CTRL_BREAK_EVENT
      PRINT "Ctrl-Break pressed"
    CASE %CTRL_CLOSE_EVENT
      PRINT "[x] Close clicked"
    CASE %CTRL_LOGOFF_EVENT
      PRINT "User logging off or restarting"
    CASE %CTRL_SHUTDOWN_EVENT
      PRINT "System shutting down"
  END SELECT
  SLEEP 1000
END FUNCTION

------------------

[Albert Richheimer]

Originally posted by Mike Doty:

    PRINT "Ctrl-C pressed.  Never got this to work."

This will never work, because RB console returns a chr$(3) in inkey$.
I also suggest to set the ConsoleHandler value %TRUE, then the control will
be handed back to the program if the [X]Close is clicked.
Here is my version.
Note: To be exact: we need to determine whether F4 or Alt-F4 is pressed, so
an (inshift and 3) would come in handy.

#compile exe
#dim all
#include "WIN32API.INC"

declare function Breakhandler(byval dwEvent as dword) as long

global gEventType as dword
global gEventFlag as long

function pbmain as long
    local lTemp as long
    local sTemp as string
    stdout "<Esc> will stop this little program"
    SetConsoleCtrlHandler codeptr(Breakhandler),1
    while %TRUE
      if gEventFlag then
         select case gEventType
           case %CTRL_BREAK_EVENT
             print "Ctrl-Break pressed"
           case %CTRL_CLOSE_EVENT
             print "[x] Close clicked"
           case %CTRL_LOGOFF_EVENT
             print "User logging off or restarting"
           case %CTRL_SHUTDOWN_EVENT
             print "System shutting down"
         end select
         gEventFlag=%FALSE
      end if
      sTemp=inkey$
      if len(sTemp) then
         select case sTemp
           case chr$(3)
             print "Ctrl-C pressed"
           case chr$(0)+chr$(62)
             print "Alt-F4 pressed"
           case chr$(27)
             print "Escape pressed - exiting program"
             exit function
           case else
             for lTemp=1 to len(sTemp)
                 stdout format$(asc(mid$(sTemp,lTemp)))+" ";
             next lTemp
             stdout""
         end select
      end if
      sleep 2
    wend
    SetConsoleCtrlHandler codeptr(Breakhandler),0
end function

function Breakhandler(byval dwEvent as dword) as long
    gEventType=dwEvent
    gEventFlag=%TRUE
    function=%TRUE
end function

Best regards
Albert

------------------
Albert Richheimer
http://consulting.richheimer.org
http://www.chlohn.ch

[This message has been edited by Albert Richheimer (edited October 29, 2006).]

[Mel Bishop]

I think I can work with that, Mike. Thanks.


------------------

[Mike Doty]

#DIM ALL
#INCLUDE "win32api.inc"
'Anyone know how to trap all events in ConsoleHandler?
'This should cover the bases
'SetConsoleMode might be used
'
DECLARE FUNCTION ConsoleHandler(BYVAL dwEvent AS DWORD) AS LONG
DECLARE FUNCTION ShutDown AS LONG
FUNCTION PBMAIN () AS LONG
  LOCAL result AS LONG

  'Can't get this to work, probably don't want anyway
  result = SetConsoleMode(CONSHNDL,%Enable_Processed_Input)    'can't get to work
  IF result = 0 THEN PRINT "Can't SetConsoleMode"              'can't get to work
  
  result = SetConsoleCtrlHandler(CODEPTR(ConsoleHandler), 1)   'add handler, true
  IF result = 0 THEN PRINT "Can't add handler"
  
  result = ASC(RIGHT$(WAITKEY$,1))  'could be 2 characters
  IF result = 3 THEN
    PRINT "Ctrl+C didn't work so shut down here"
  ELSEIF result = 62 THEN
    PRINT "Alt+F4 didn't work, so shut down here"
  ELSE
      PRINT "result" ; result
  END IF
  ShutDown
  result = SetConsoleCtrlHandler(CODEPTR(ConsoleHandler), 0)  'remove handler, false
  IF result = 0 THEN
     PRINT "Didn't end handler cleanly"
  ELSE
    PRINT "Handler shutdown correctly"
  END IF
  SLEEP 2000
END FUNCTION

FUNCTION ConsoleHandler(BYVAL dwEvent AS DWORD) AS LONG
  PRINT "ConsoleHandler"
  'Alt + F4 not trapped here, Ctrl-C not working either
  SELECT CASE dwEvent
    CASE %CTRL_C_EVENT
      PRINT "Ctrl-C pressed."                    'does NOT get called here
      ShutDown
    CASE %CTRL_BREAK_EVENT                       'does NOT get called here
      PRINT "Ctrl-Break pressed"
      ShutDown
    CASE %CTRL_CLOSE_EVENT                       'works
      PRINT "[x] %CTRL_CLOSE_EVENT"
      ShutDown
    CASE %CTRL_LOGOFF_EVENT                      'works
      PRINT "User logging off or restarting"
      ShutDown
    CASE %CTRL_SHUTDOWN_EVENT                    'works
      PRINT "System shutting down"
      ShutDown
  CASE ELSE
      PRINT "dwEvent was something else" + STR$(dwEvent)
      ShutDown
  END SELECT
  SLEEP 1000
END FUNCTION

FUNCTION ShutDown AS LONG
  STATIC AlreadyShutDown AS LONG
  IF AlreadyShutDown THEN
     BEEP
     PRINT "ShutDown: Already Shutdown, have never seen this"
     SLEEP 500
     EXIT FUNCTION
  END IF
  PRINT "ShutDown:"
  AlreadyShutDown = 1
  SLEEP 500
END FUNCTION

------------------

[Mike Doty]

Albert,

CASE %CTRL_CLOSE_EVENT                       'works
      PRINT "[x] %CTRL_CLOSE_EVENT"
      ShutDown

If FUNCTION = 1 is added above, windows opens a dialog box
saying the system needs more time to end (in my code.)"


------------------

[Albert Richheimer]

Originally posted by Mike Doty:
Albert,
If FUNCTION = 1 is added above, windows opens a dialog box
saying the system needs more time to end (in my code.)"

Right. This is the reason for the return value = 1. If you want to close down
the program immediately you may return 0.

Best regards
Albert


------------------
Albert Richheimer
http://consulting.richheimer.org
http://www.chlohn.ch