I have been working all morning on filtering to get the Elements where ‘BOM Level’ has a Null values. I’ve checked in Revit… the BOM Level is simply not filled in on the Element.
The intent is to warn the user that these elements need some attention.
A final look back at my graph before finishing this post showed that I can use == node with null in a code block.
Thoughts?
What you are doing there is actually looking for an empty string “”, this is not the same as a Null value.
Use the Object.IsNull node
That’s what I thought also early on… using empty string made complete sense to me as well… but when I tried it… it didn’t work. That’s when I put up the post.
See below with various approaches including Object.IsNull Node and empty string approach. Using Null to == node and Object.IsNull Node both work.
It seems Dynamo/Revit doesn’t see Zero Length Strings like other languages. Equal with “” in Lisp is a Zero Length String. Perhaps Zero Length String and Empty String are two different things?
Thanks for the tip… Object.IsNull Node is more elegant in a single node instead of using == with null in a code block.
