Is it a bad idea to test for Nulls?

[back2basic]

I probably wouldn't ask this question if I didn't have a problem. I am testing text fields that are blank (I think are blank). The watch window shows the variable returned as "" However the IFisNull fails?

At first this was all working and the test passed with "" returned. What has happened to the DB? Should I fill all fields in this column with blanks and test for an empty string?

Do I need to reset something in the table or combo Box at the start of the VB module called from the form?

Baffelled
Thank you for any help.

Dale

 

[pbaldy]

The test here works for both Null and a zero length string ("").

http://www.baldyweb.com/BeforeUpdate.htm

 

[back2basic]

Thank you pbaldy, You have helped me a lot. My event procedure is afterUpdate and I am having a problem cancelling. I think I'll switch, Will that make any difference with the problem I am having with the IfisNull test failing?

 

[pbaldy]

If you're validating data, I'd use the before update event. I really only gave that link for the test it used though.