How to modify readonly parameters

[mahshid.motie]

Hi everyone 🙂

I have a revit file and I want to modify the base and top constraints of the walls. When I run the API I receive an error (for some of the walls, not all) which says these parameters are readonly. When I checked those walls I recognized that the walls with readonly error have the parameter line-location while the others doesnt have. Can this be relevant? Do you know how can I still modify these readonly parameters? 

Thanks in advance

[jeremytammik · Accepted solution]

Well, a read-only parameter is read-only, so it cannot be modified.

That is the point  🙂

Some of these parameters hold values that are driven by other constraints built into the BIM.

So, you need to discover and understand what these constraints are, and then modify whatever is driving them.

The most efficient way to research this is mostly to start by modifying the model manually via the end user interface and observe the changes in the database via API-based db exploration tools such as RevitLookup:

https://thebuildingcoder.typepad.com/blog/2017/01/virtues-of-reproduction-research-mep-settings-onto...

[mahshid.motie]

Thanks for the answer Jeremy 😉

I explain the reason why I had readonly error in my case in case some one has the same problem. 

In the model that I have there are some walls that have top level : unconnected which results in level.id of (-1) associated to their top level constraints. Therefor in those cases I only modified the bottom level constraints.