I've tested this solution and I don't think it is correct.
I've just come across a use case for inventory detail subrecord on a Bin Transfer. Since this isn't supported yet we will not be able to use io for this need. Hopefully it will come soon.
Thanks for this! Exactly what I needed!
Update on this for anyone that is interested - since I am pulling the data from a saved search in NetSuite, I used the SQL expression LPAD. An example of this is: LPAD({linesequencenumber}, 4, '0')...
Thanks, David. I tried this in the handlebars editor and it works when the string is a text value. But then I tried it with a numeric value and it only returned '0000'. Then I tried it in the File...