Conditional Formating - Validation

  • Thread starter Thread starter Guest
  • Start date Start date
G

Guest

I have 2 fields on the form. If one is filled in, the other one needs to be
as well.
However, they both can be blank.

Any ideas?
 
You can use the Before Update event of the form to check for this condition:
Warning! Untested Air Code

If (IsNull(Me.TextBox1) And Not IsNull(Me.TextBox2)) Or _
(Not (IsNull(Me.TextBox1) And IsNull(Me.TextBox2))) Then
Then MsgBox "Both Text Boxes Must Be Filled In"
Cancel = True
End If
 
Let me introduce you to the wonders of a truth table

Length Length
Field1 Field2 Result Action
0 0 VALID No Information Present
0 1 VALID Information missing
1 0 VALID Information missing
1 1 VALID Information present

From there just build your If...Thens as in

If Len(Field1) = 0 AND Len(Field2) = 0 Then

If (Len(Field1) = 0 AND Len(Field2) > 0) OR (Len(Field1) > 0 AND
Len(Field2) = 0) Then

If Len(Field1) > 0 AND Len(Field1) > 0 Then

In this situation, I assumed that the validation is simple in that the a
character is in either field. If the validation criteria is different,
adapting the above, shouldn't be that difficult.

For more on truth tables...

http://en.wikipedia.org/wiki/Truth_table

David H
 
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