[AccessD] Excel Question

Hi,
anyone with a quick answer to this one:

Excel appears to treat blank cell as zero

I've created a function that tests the value in a cell (say A1) using Select
Case and delivers a value in another cell (say B1) depending on value in
cell.

The function tests on values 0,1,2,3,4,5,6,7,8,9 and responds with a message
if any other value is entered.

So far so good!

Now, the annoying part is that a blank value - null - is treated as ZERO by
the function.


How do I turn this off - so that a the value of a blank cell is treated as
null ???

Regards


Borge,