C#

private void OnAddItem()
{
    SubItemViewModel subVM = new SubItemViewModel(Key, null, false);
    IDisposable ss = Observable.FromEventPattern(subVM.Save, "ExecuteEnd").Take(1).Subscribe(x => { LoadList(); });
    SubControl ctrl = new SubControl();
    ctrl.DataContext = subVM;
    WorkspaceUserControlWindow w = new WorkspaceUserControlWindow(ctrl);
    w.Title = subVM.DisplayTitle ?? Key.Value + " - Add Item";
    Observable.FromEventPattern(w, "Closed").Take(1).Subscribe(x => { if (ss != null) ss.Dispose(); });
    w.Show();
}

IDisposable ss= Observable.FromEventPattern(subVM.Save, "ExecuteEnd").Take(1).Subscribe(x => { LoadList(); });

public static void Logging(string logMessage, string user)
        {
            using (Writer)
            {
                Writer.Write("\r\nLog Entry : ");
                Writer.Write(
                    "{0} {1}\r\n user: {2}",
                    DateTime.Now.ToLongTimeString(),
                    DateTime.Now.ToLongDateString(),
                    user);
                Writer.WriteLine(": {0}", logMessage);
                Writer.WriteLine("-------------------------------");
            }
        }