DetailCurve.ByCurve deleting previous linework

I have a file that creates a series of curves between selected elements by using DetailCurve.ByCurve.
Every time I run the file, new curves are created, but those created in the previous run are deleted.
How do I prevent the deletion on each run?


Edit: I have found that by duplicating the lines in Revit (i.e. copying to the same place), I can run the file on other elements. Is there a way I can avoid this duplicating step?

Hi @troy_troy
My understanding is this:
If Dynamo gets curves by selecting objects from Revit, the ID is retained.
So when running the graph the next time, objects created before (with the same ID) are updated instead of being recreated. By this logic, duplicating will work as that means another set of objects with different IDs…

I had faced a similar issue when creating Views in Dynamo using levels from Revit.

Will also await the experts to confirm if my understanding is (in)correct.
Meanwhile, is it possible to create those base curves from Dynamo itself?

Thanks Chandrasekar. I will have a look into IDs and see if I can create a new one each time (or something).
I’m not sure I understand your question. Here is how I am generating the connecting lines for a planting plan. I am very new to Dynamo.

Hi, here are two reference posts on this topic:

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Thanks Yna_Db,

Your post has certainly helped me understand the problem and limitations better.

I know that this is an old topic, but what I found to work was to set the final wall element to ‘Is Output’ (right click menu). Then when run from the player it commits the addition and allows a different selection to be made.

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