Lightbox Check start/end date when end date less than start date

Lightbox Check start/end date when end date less than start date: in this scenario scheduler equals the start and ending day and saves, instead we want to emit an alert with a message, how can be done?

Hi,

You can check it in the onEventSave event.
https://docs.dhtmlx.com/scheduler/api__scheduler_oneventsave_event.html

Check end_date value, show an alert and “return false” in the handler when it’s necessary.