The eventSelectCallBack() method executes the server-side EventSelect handler using an AJAX callback (ASP.NET WebForms, ASP.NET MVC, Java).
DayPilot.Month.eventSelectCallBack(e, change[, data]);e (DayPilot.Event) - reference to the event object
change - change type ("selected" | "deselected")
data (object) - custom data to be sent to the server-side event handler
dp.eventSelectCallBack(e, "selected", data);