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eventResourceField

Normally Event Objects are linked to resources via the event’s resourceId field. However, if you wish to use another field name, you may specify it with eventResourceField.

This setting has been deprecated. Use eventDataTransform instead.
$('#calendar').fullCalendar({
  resources: [
    {
      id: 'a',
      title: 'Room A'
    }
  ]
  eventResourceField: 'roomId',
  events: [
    {
      id: '1',
      roomId: 'a',
      title: 'Meeting',
      start: '2015-02-14'
    }
  ]
});