Opc.Ua.SampleClient.ClientPage.Window_PageClosing C# (CSharp) Method

        async void Window_PageClosing(object sender, RoutedEventArgs e)
        {
            if (m_masterPage == null && m_pages.Count > 0)
            {
                MessageDlg dialog = new MessageDlg("Close all sessions?", MessageDlgButton.Yes, MessageDlgButton.No);
                MessageDlgButton result = await dialog.ShowAsync();
                if (result != MessageDlgButton.Yes)
                {
                    return;
                }
            }

            BrowseCTRL.Clear();

            for (int ii = 0; ii < m_pages.Count; ii++)
            {
                if (Object.ReferenceEquals(m_pages[ii], sender))
                {
                    m_pages.RemoveAt(ii);
                    break;
                }
            }
        }