Tag of DataType.Float8 does not support "null"

Hello Forum,
I have implemented a tag provider that builds upon SimpleTagProvider. So far so good, but there is a problem due to some requirements that I have.

I need to support tags that have numeric values (such as DataType.Float8) but that accepts also a “null” or empty value. Is that possible?

I could use DataType.String (and conventionally consider “null” an empty string), but this way I think I would loose some useful “numberness” validations from the platform.

Any thoughts?


Maybe you could use NaN as your null/empty value?

Hi Kevin, thanks but that does not help.
The problem is with the Tag Browser. If the type is Float8, I am allowed only to set a number. I cannot set an empty value, nor I can set NaN, as you suggested.


Ah, yeah. You’re not going to be able to enter any kind of non-numeric tag value from the tag browser. Even if you use String you wouldn’t be able to set a null value that way.

However, in both cases you could set the empty/NaN/null/whatever value via scripting.