GridView commandfield button based on recordset value?

[11D.Universe]

I've got a sql table containing a nullable int field named DataID.
The field is displayed as part of a GridView.

Is it possible to create a single CommandFieldButton column in the
GridView containing a button where the text displayed is a function of
the DataID field contents? For example, let's say if DataID is NULL,
the button in that row would read "Fill" and if the DataID is not
NULL, the button would read "Go"?

So, in the above example the grid would look like:

Button DataID
-------- ---------
Fill Null
Go 123
Fill Null
Go 55