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transientmdriven

MDriven: Transient instance of persistent class

In MDriven I have a persistent class that I need to create a transient instance of.

Is this possible?

I do know that a workaround would be to create as usual and then discard it.

Clarification 2018-02-02 17:04 UTC+1:
I would need to do this without adding anything to the model, compile time.

Solution

  • Yes you are correct - it is not possible to change a class to become transient in runtime.

    You can however subclass it... And make the subclass transient... I have had that exact need myself and solved it that way.

    The MonthDemandSupplyCorrection is persistent - but the MDSC_Placeholder is not

    Example: The MonthDemandSupplyCorrection is persistent - but the MDSC_Placeholder is not

    Update: Since the requirement was clarified to be "not known in design time" - a better answer is to create an ordinary instance and avoid saving it. This can be ensured with the undo-service and memory transactions like this:

      EcoSpace.Undo.StartTransaction();
  try
  {
     //Any changes you need
  }
  finally
  {
    EcoSpace.Undo.RollbackTransaction(); 
  }