I want to use VBA to check to see if a formulas has any references to blank
cells.

So if my formulas is

=A1+SUM(B2:B30)/Average(C1:C30)+Opcost

I want to know if either A1 is blank, any of the array items in the SUM or
Average are blank, if named cell Opcost is blank etc

Is there a way to evaluate the formula propertly of the cell object to test
for blanks? Am I wandering into Regular Expression territory with this one?
Or can I do it with VBA?

Thanks