An activated time range selection can display a context menu on right click.

ASP.NET WebForms

 
<DayPilot:DayPilotCalendar runat="server" id="DayPilotCalendar1"
  ...
  ClientObjectName="dpc"
  ContextMenuSelectionID="DayPilotMenuSelection"
/>

<DayPilot:DayPilotMenu ID="DayPilotMenuSelection" runat="server" CssClassPrefix="menu_default" >
  <DayPilot:MenuItem Action="JavaScript" JavaScript="dpc.timeRangeSelectedCallBack(e.start, e.end, e.resource);"
      Text="Create new event (JavaScript)" />
  <DayPilot:MenuItem Action="PostBack" Command="Insert" Text="Create new event (PostBack)" />
  <DayPilot:MenuItem Action="CallBack" Command="Insert" Text="Create new event (CallBack)" />
  <DayPilot:MenuItem Text="-" Action="JavaScript"></DayPilot:MenuItem>
  <DayPilot:MenuItem Action="JavaScript" JavaScript="alert('Start: ' + e.start + '\nEnd: ' + e.end + '\nResource id: ' + e.resource);"
      Text="Show selection details" />
  <DayPilot:MenuItem Action="JavaScript" JavaScript="dpc.clearSelection();" Text="Clean selection" />
</DayPilot:DayPilotMenu>

ASP.NET MVC

 
@Html.DayPilotMenu("menu_selection", new DayPilotMenuConfig {
  Items = new DayPilot.Web.Mvc.MenuItemCollection
  {
    new DayPilot.Web.Mvc.MenuItem { Text = "Open", Action = MenuItemAction.JavaScript, JavaScript = "alert(e.start + ' ' + e.end + ' ' + e.resource);"}
  }
  })

@Html.DayPilotCalendar("dpc", new DayPilotCalendarConfig {
  BackendUrl = ResolveUrl("~/Calendar/Backend"),
  ContextMenuSelection = "menu_selection",
})