OptionC.cs

/* Martin had this suggestion for an improvement */

public class UnitOfWork : IUnitOfWork
{
  private UnitOfWork() {}
  
  public static Do(Action<IUnitOfWork> action)
  {
    action(new UnitOfWork());
  }
  
  public T Get<T>() {}
}

public enum TransactionResult { Commit, Rollback };

public class MutableUnitOfWork : UnitOfWork, IMutableUnitOfWork
{
  private MutableUnitOfWork(){}
  
  public static Do(Func<IMutableUnitOfWork, TransactionResult> action)
  {
    try
    {
      if(action(new MutableUnitOfWork()) == TransactionResult.Commit)
        Commit();
    }
    catch(Exception ex)
    {
      /* Log? */
    }
    
    Rollback();
  }
  
  public void Save<T>(T obj) {}
  
  private void Commit() {}
  private void Rollback() {}
}


public void SomeAction()
{
  MutableUnitOfWork.Do(uow =>
  {
    DoStuff(uow);
    var floor = uow.Get<Floor>(1);
    floor.Name = "Test";
    uow.Save<Floor>(floor);
    if(SessionExpired)
      return TransactionResult.Rollback;
    return TransactionResult.Commit;
  });
}