Stop Deletes/Resize/Any changes of any previous Events

How to stop any changes of all the events which have elapsed from current date. Suppose events has been added then changes like resizing | deleting | updating should be possible for all events in past.

i think the only way to achieve this is to handle update events manually, the code may be like following[code] function isNotPastEvent(event_id){
var date = scheduler.getEvent(event_id).start_date;
if(date.valueOf() < new Date().valueOf()){
dhtmlx.message(“Past event”);
return false;
return true;

	scheduler.attachEvent("onBeforeLightbox", isNotPastEvent);
	scheduler.attachEvent("onClick", isNotPastEvent);
	scheduler.attachEvent("onBeforeEventChanged", function(event){
		return isNotPastEvent(;