SchedulerControl.AllowAppointmentDelete Event

using DevExpress.XtraScheduler;
// ... 

private void schedulerControl1_AllowAppointmentDelete(object sender, 
    AppointmentOperationEventArgs e) {
   // Allow only the user who created this appontment to delete it. 
   e.Allow = CanUserModifyThisAppointment(e.Appointment);
}
private void schedulerControl1_AllowAppointmentEdit(object sender, 
    AppointmentOperationEventArgs e) {
   // Allow only the user who created this appontment to modify it. 
   e.Allow = CanUserModifyThisAppointment(e.Appointment);
}
// Determine if the current user is the same  
// as the one who created the specified appointment  
bool CanUserModifyThisAppointment(Appointment apt) {
   object obj = apt.CustomFields["Owner"];
   if (obj == null)
      return true;
   string appointmentOwner = obj.ToString();
   if (appointmentOwner == String.Empty)
      return true;
   return (String.Compare(appointmentOwner, tbUserName.Text, true) == 0);
}

Imports DevExpress.XtraScheduler
' ... 

Private Sub schedulerControl1_AllowAppointmentDelete(ByVal sender As Object, _
ByVal e As AppointmentOperationEventArgs)
   ' Allow only the user who created this appontment to delete it. 
   e.Allow = CanUserModifyThisAppointment(e.Appointment)
End Sub 
Private Sub schedulerControl1_AllowAppointmentEdit(ByVal sender As Object, _
ByVal e As AppointmentOperationEventArgs)
   ' Allow only the user who created this appontment to modify it. 
   e.Allow = CanUserModifyThisAppointment(e.Appointment)
End Sub 
' Determine if the current user is the same  
' as the one who created the specified appointment  
Private Function CanUserModifyThisAppointment(ByVal apt As Appointment) As Boolean 
   Dim obj As Object = apt.CustomFields("Owner")
   If obj Is Nothing Then 
      Return True 
   End If 
   Dim appointmentOwner As String = obj.ToString()
   If appointmentOwner = String.Empty Then 
      Return True 
   End If 
   Return (String.Compare(appointmentOwner, tbUserName.Text, True) = 0)
End Function