Family Parameter IsInstance incorrect

[JasonKunkel]

I saw another older post with no replies with the same issue.

https://forums.autodesk.com/t5/revit-api-forum/instance-parameter-or-not/td-p/9380442

If I go through my own add-in, or if I use Revit Lookup, I see the same behavior.

In a family file going through Family Manager, when I look at parameters the IsInstance property might be wrong. If there is no value in the parameter, it returns False even if through the UI it is showing as an Instance parameter. As soon as I add a value, Lookup and my add-in report IsInstance as true. I was testing with a boolean parameter. So it was in the "null" state when it reported wrong.

Am I missing something? Or is this busted?

[jeremytammik · Accepted solution]

Dear Jason,

Thank you for your report.

That does indeed sound rather strange.

I logged the issue REVIT-167409 [FamilyParameter IsInstance erroneously returns false] with our development team for this on your behalf as it requires further exploration and possibly a modification to our software. Please make a note of this number for future reference.

You are welcome to request an update on the status of this issue or to provide additional information on it at any time quoting this change request number.

This issue is important to me. What can I do to help?

This issue needs to be assessed by our engineering team and prioritised against all other outstanding change requests. Any information that you can provide to influence this assessment will help. Please provide the following where possible:

• Impact on your application and/or your development.
• The number of users affected.
• The potential revenue impact to you.
• The potential revenue impact to Autodesk.
• Realistic timescale over which a fix would help you.
• In the case of a request for a new feature or a feature enhancement, please also provide detailed Use cases for the workflows that this change would address.

This information is extremely important. Our engineering team have limited resources, and so must focus their efforts on the highest impact items. We do understand that this will cause you delays and affect your development planning, and we appreciate your cooperation and patience.

I hope this helps.

Best regards,

Jeremy