It is possible to use a special mode where the user can select an exact position inside the target cell when moving the event (relative to other events in the target cell). 

You can use this feature to manage priority ordering.

Moving modes

Default moving mode (moving to time cell)

monthly-calendar-move-to-cell.png

Moving to a position inside a cell

monthly-calendar-move-to-position.png

You can enable this mode by using EventMoveToPosition property. The selected position will be available in EventMove event handler as e.Position.

You should store the position in a separate database field and use it for event sorting.

ASP.NET WebForms

.aspx

<DayPilot:DayPilotMonth runat="server" id="DayPilotMonth1"
  ...
  EventMoveToPosition = "true"
/>

.aspx.cs

protected void DayPilotMonth1_EventMove(object sender, EventMoveEventArgs e)
{
  // update the db here, reload events
  DayPilotMonth1.UpdateWithMessage("Event moved to position: " + e.Position);
}

Demo

ASP.NET MVC

The target position is available in OnEventMove handler as e.Position (starting at index 0).

Example

View

@Html.DayPilotMonth("dpm", new DayPilotMonthConfig {
  BackendUrl = ResolveUrl("~/Month/Backend"),
  ...
  EventMoveToPosition = true
})

Backend Controller

protected override void OnEventMove(EventMoveArgs e)
{
  // update the db here, reload events
  UpdateWithMessage("Moved to position: " + e.Position);
}

Demo

JavaScript

<div id="dp"></div>
<script type="text/javascript">
  var dp = new DayPilot.Month("dp");
  dp.eventMoveToPosition = true;
  dp.onEventMoved = function(args) {
    dp.message("Event moved to position: " + args.position);
  }
  // ...
  dp.init();
</script>