on_event

/*
 *  call-seq:
 *     WIN32OLE_EVENT#on_event([event]){...}
 * 
 *  Defines the callback event.
 *  If argument is omitted, this method defines the callback of all events.
 *    ie = WIN32OLE.new('InternetExplorer.Application')
 *    ev = WIN32OLE_EVENT.new(ie, 'DWebBrowserEvents')
 *    ev.on_event("NavigateComplete") {|url| puts url}
 */
static VALUE
fev_on_event(argc, argv, self)
    int argc;
    VALUE *argv;
    VALUE self;
{
    return ev_on_event(argc, argv, self, Qfalse);
}