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Event Object

A plain JavaScript object that FullCalendar uses to store information about a calendar event. Here are its properties:

id String/Integer. Optional Uniquely identifies the given event. Different instances of repeating events should all have the same id.
title String. Required. The text on an event's element
allDay true or false. Optional. Whether an event occurs at a specific time-of-day. This property affects whether an event's time is shown. Also, in the agenda views, determines if it is displayed in the "all-day" section. If this value is not explicitly specified, allDayDefault will be used if it is defined. If all else fails, FullCalendar will try to guess. If either the start or end value has a "T" as part of the ISO8601 date string, allDay will become false. Otherwise, it will be true. Don't include quotes around your true/false. This value is a boolean, not a string!
start The date/time an event begins. Required. A Moment-ish input, like an ISO8601 string. Throughout the API this will become a real Moment object.
end The exclusive date/time an event ends. Optional. A Moment-ish input, like an ISO8601 string. Throughout the API this will become a real Moment object. It is the moment immediately after the event has ended. For example, if the last full day of an event is Thursday, the exclusive end of the event will be 00:00:00 on Friday!
url String. Optional. A URL that will be visited when this event is clicked by the user. For more information on controlling this behavior, see the eventClick callback.
className String/Array. Optional. A CSS class (or array of classes) that will be attached to this event's element.
editable true or false. Optional. Overrides the master editable option for this single event.
startEditable true or false. Optional. Overrides the master eventStartEditable option for this single event.
durationEditable true or false. Optional. Overrides the master eventDurationEditable option for this single event.
resourceEditable true or false. Optional. Overrides the master eventResourceEditable option for this single event.
rendering Allows alternate rendering of the event, like background events. Can be empty, "background", or "inverse-background"
overlap true or false. Optional. Overrides the master eventOverlap option for this single event. If false, prevents this event from being dragged/resized over other events. Also prevents other events from being dragged/resized over this event.
constraint an event ID, "businessHours", object. Optional. Overrides the master eventConstraint option for this single event.
source Event Source Object. Automatically populated. A reference to the event source that this event came from.
color Sets an event's background and border color just like the calendar-wide eventColor option.
backgroundColor Sets an event's background color just like the calendar-wide eventBackgroundColor option.
borderColor Sets an event's border color just like the the calendar-wide eventBorderColor option.
textColor Sets an event's text color just like the calendar-wide eventTextColor option.
resourceId String. The id of a Resource that this event is associated with. (requires premium)
resourceIds Array of strings. When an event is associated with multiple resources, each element of this array is the id of a Resource. (requires premium)

Non-standard Fields

In addition to the fields above, you may also include your own non-standard fields in each Event Object. FullCalendar will not modify or delete these fields. For example, developers often include a description field for use in callbacks such as eventRender.

Events and Dates

To summarise, the value of start is the inclusive start date of the event. The event continues up to the specified end date. This value is exclusive because it is the cut-off point of the event. FullCalendar handles these dates in the same way as discussed in the iCalendar Specifications (RFC 5545) and Google Calendar API documentation.

Furthermore, there is a nextDayThreshold option which can be set on the calendar itself. It is ignored when allDay is true. However, when allDay is false, the nextDayThreshold property allows an override of the default behaviour of exclusive end dates by setting the cut-off point for the event to be rendered on that date. The default is 09:00:00.