# eventDataTransform

> FullCalendar v1 documentation, for an old release. Web version: https://legacy.fullcalendar.io/v1/eventDataTransform
>
> Latest version (v7): https://fullcalendar.io/docs/eventDataTransform.md

Transforms custom data into a standard [Event Object](https://legacy.fullcalendar.io/v1/event-object.md).

<div class='spec' markdown='1'>
function( *eventData* ) {}
</div>

This hook allows you to receive arbitrary event data from a JSON feed or any other [Event Source](https://legacy.fullcalendar.io/v1/event-source-object.md) and transform it into the type of data FullCalendar accepts. This let's you easily accept alternative data formats without having to write a completely custom [events function](https://legacy.fullcalendar.io/v1/events-function.md).

This function is called once per received event. `eventData` is the event data that has been receieved. The function must return a new object in the [Event Object](https://legacy.fullcalendar.io/v1/event-object.md) format.