# OnClientAppointmentEditing

The **OnClientAppointmentEditing** client-side event is called before an appointment is edited.

Two parameters are passed to the event handler:

* **sender** is the scheduler client object.

* **eventArgs** has the following methods:

* **get_appointment()** - returns the appointment instance.

* **get_editingRecurringSeries()** returns **True** if theuser is trying to edit a series to which the appointment belongs, **False** if the user istrying to edit a single occurrence of an appointment.

* **set_cancel()** lets youpermit or block the edit to the appointment. Calling **set_cancel(true)** stops the edit,while **set_cancel(false)** allows the scheduler to bring up an edit form or in-line editorfor the appointment.

## Example

This example prevents the user from editing an appointment's series:

```ASP.NET
<script type="text/javascript">   
function OnClientAppointmentEditing(sender, eventArgs)
{
	if(eventArgs.get_editingRecurringSeries())
		  eventArgs.set_cancel(true);
}
</script>
<telerik:RadScheduler
 ID="RadScheduler1"
 runat="server"  
 OnClientAppointmentEditing="OnClientAppointmentEditing"
 DataSourceID="AppointmentsDS" />     
	
```

## See Also

* [Replace the Edit Form](https://www.telerik.com/products/aspnet-ajax/documentation/controls/scheduler/how-to/replace-the-edit-form)