[2005] Design Time "Validation"

Using <System.Obsolete("Warning Message", false)> you can deprecate controls. My situation is similiar, but a little different. I have values being assigned to y custom object's properties that I would like to validate with RegEx.

I.E.
They pass "Cheesetype=cheddar;Cracker=wheatthin" to a style property during design (as a constant expression); I would like to be able to use similiar design-time functionality to say (based on regex), use the object's property "Cheesetype" instead of inline attributes as a warning.

Any ideas or a direction?

To clarify, I have the regex I need and know how to use <system.componentmodel.attributeusage(...> to limit the input to a constant expression; I just am lost on applying the regex to the constant expression to the design time IDE.

Many thanks.

bumpers