automatically update the attributes of a dynamic block

[paolo fava]

I created a dynamic 2x36w and 2x58w ceiling block with dynamic control ironing length, with the modified attribute description, I would like to make sure that when I choose the option plaf 2x36w or 2x58w automatically update the attribute text:
Thank you.

 

[Giuseppe Mauro]

If you don't need to extract data, you can create a block with a visible parameter instead of ironing it.
you will have a 2x36 visible (with 3x36 text) and a 2x58 with longer lamp and 2x58 text

but in this way you lose the extraction of the data from the attribute (if you use it for extraction)