protected void SelectCheckBox_OnCheckedChanged(object sender, EventArgs e)
 {
     if ((sender as CheckBox).Checked)
     {
         AttendRegistrationEngine.CopyParticipants(CurrentData);
     }
 }
        protected void Copy_OnClick(object sender, EventArgs e)
        {
            if (IsChecked())
            {
                AttendRegistrationEngine.CopyParticipantsRemove(CurrentData);
            }
            else
            {
                AttendRegistrationEngine.CopyParticipants(CurrentData);
            }

            Copy.DataBind();
        }
        protected void CheckAll_OnClick(object sender, EventArgs e)
        {
            int numberOfCopied = AttendRegistrationEngine.GetOrCreateParticipantsClipboard().Count;

            if (numberOfCopied > 0)
            {
                AttendRegistrationEngine.CopyParticipantsRemoveAll();
            }
            if (numberOfCopied == 0)
            {
                List <IParticipant> contents = Participants;
                contents = FilterStatus(contents);
                contents = FilterEmail(contents);
                contents = FilterSessions(contents);
                contents = FilterSearch(contents);

                foreach (var IParticipant in contents)
                {
                    AttendRegistrationEngine.CopyParticipants(IParticipant as IParticipant);
                }
            }
        }