/// <summary>
        /// Sends acknowledgement for an event notification.
        /// </summary>
        private void AcknowledgeMI_Click(object sender, System.EventArgs e)
        {
            try
            {
                // get current selection.
                TsCAeEventNotification[] notifications = new TsCAeEventNotification[notificationsLv_.SelectedItems.Count];

                for (int ii = 0; ii < notifications.Length; ii++)
                {
                    notifications[ii] = (TsCAeEventNotification)notificationsLv_.SelectedItems[ii].Tag;
                }

                // show dialog.
                bool result = new AcknowledgerEditDlg().ShowDialog(mServer_, notifications);

                // delete events if successful.
                if (result)
                {
                    DeleteMI_Click(sender, e);
                }
            }
            catch (Exception exception)
            {
                MessageBox.Show(exception.Message);
            }
        }
        /// <summary>
        /// Acknowledges an event.
        /// </summary>
        private void AcknowledgeBTN_Click(object sender, System.EventArgs e)
        {
            try
            {
                bool result = new AcknowledgerEditDlg().ShowDialog(mSubscription_.Server, new TsCAeEventNotification[] { mNotification_ });

                if (result)
                {
                    acknowledgeBtn_.Enabled = false;
                }
            }
            catch (Exception exception)
            {
                MessageBox.Show(exception.Message);
            }
        }