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eventChange

Called after an event has been modified in some way.

function( changeInfo )

This fires after any Event Object setter method is called, like setStart. It is also called after an event has been dragged or resized. eventChange will fire after eventDrop and eventResize.

The changeInfo argument has the following properties:

event an Event Object with the updated changed data
relatedEvents an array of other related Event Objects that were also affected. an event might have other recurring event instances or might be linked to other events with the same groupId
oldEvent an Event Object with data prior to the change
revert a function that can be called to reverse this action