Column Invisibility

Hey,

I am retrieving values from a database I have setup in sql server. Basically I want to make a column invisible if the value is null.

Here is the code I tried, but it didn't work.

=IIf(Fields!FundingCode.Valueisnothing,True, False)

I would greatly appreciate the help

a column of what? Datagrid, Gridview? What?