Novice User - First script not working

Please go easy on me as I have only started looking at Dynamo a few hours ago. I am trying to change Structural Material wording in my Str Steel Columns. The last 2 blocks don’t work. This is probably relatively easy for this group but please could someone tell me where I am going wrong and how I can fix the script?

Well - you’re inputting a function into a string.
If you open the little yellow note above your error - that will give you the traceback information and help in debugging.

Screenshot is a bit hard to read because all the node titles are ‘missing’, but as far as i can tell
you are not feeding the node correctly.

Hopefully that’s a bit clearer?

String from object is not getting an object. Nor is that probably what you want to do.
You’ll need to first filter the list of items to be changed using a FilterByBooleanMask based on your parameter criteria.
Then just make the changes to the items in that list.

There really isn’t a search and replace in the way you are thinking about it.

Look around here and you’ll find plenty of good examples.

Also worth noting that OP wants to replace a material (at least looks like it).
That works a bit different then simply wiring the name of the material into
the value of the Element.SetParameterByName node.

Here, this will get you started.

DynamoBIM.dyn (18.5 KB)

Thank you, Much appreciated.