WideStudio Programming Guide	WideStudio Index Table of contents

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How to select the key events on the input field

You can select or reject/convert the key events on the input field with the event procedure by the WSEV_KEY_HOOK trigger.

(* A WSEV_KEY_HOOK sample procedure. *)
(* Set the input field with the WSEV_KEY_HOOK trigger. *)
...

let hookop obj =
  let key = get_int (_WSGIappKeyboard '() -> getKey () ) in
  if (((key >= get_int _WSK_0) && ( key < get_int _WSK_9)) ||
     ((key >= get_int _WSK_KP_0) && ( key < get_int _WSK_KP_9)) ||
     (key = get_int _WSK_plus)  || (key = get_int _WSK_minus) ||
     (key = get_int _WSK_BackSpace) || (key = get_int _WSK_Delete) || (key =
get_int _WSK_Insert) ||
     (key = get_int _WSK_space) || (key = get_int _WSK_Up) || (key = get_int
_WSK_Down) ||
     (key = get_int _WSK_Left) || (key = get_int _WSK_Right) || (key = get_int
_WSK_Return) ) then begin
    (* dispatches.. *)
  end else begin
    (* Reject the other. *)
    ignore(_WSGIappKeyboard '() -> setKey (0));
  end
  ()

let _ = Callback.register "hookop" hookop

This sample of the input field shows how to choose the key event. _WSGIappKeyboard '()->setKey(0) reject the key event which you do not need.