Friday, February 27, 2015

Shared Parameters are Shared Definitions

We tend to think of Shared Parameters as a thing, equal to Family and Project parameters. I've even described them as such in past posts on the subject. If I'm very picky and technical they are not a thing, they are a device, a parameter definition, shared to either create a family parameter or project parameter or both.

Yes, they help us create a Family or Project parameter, but on their own they are nothing, they only exist in a text file. That text file only defines their name and data type, nothing else. Okay technically the file has a little more data in it than that but it's only used internally by Revit. It doesn't mean they have standing or truly exist on their own. We have to apply them to Family/Project parameters for them to mean something, be something, be useful.

Written another way, a family parameter (either component or system) can be created from a shared parameter and a project parameter likewise but there are no shared parameters that aren't one or the other.

This is why I regard them as a definition stored in a dictionary, the Shared Parameter file.


RevitCat said...

Shared Parameters may not be "things" but they have mysterious powers that affect scheduling and tagging; not to mention their hidden "GUIDs" that distinguish between apparently identically named shared parameters.

How frustrating that they are not all pervasive in Revit. For example, you cannot use them in annotation families (tags), key schedules or calculated values in schedules, to name but 3 situations where they would be invaluable for enforcing consistency, and allowing proper tagging.

Paul F. Aubin said...

Hi Steve:
I like your dictionary analogy, but here's another if you are interested.

I often describe them as a recipe. Like one that you might use to bake a pie. The recipe is only needed when you actually make the pie. You do not need it to enjoy the pie. If you bake some apple pies from your favorite recipe, and then throw away the recipe while cleaning up, you still have the pies (at least until the kids get home from school…) you will just have a hard time baking another pie the next time.

Steve said...

and don't leave out the cinnamon ;)

Paul F. Aubin said...

Opened myself up for that didn't I? :-)