Conditional formatting for a empty field

[Bradex]

I have a combo box1 a/b/c.
If any of these is selected, combobox2 should get enabled.

I disabled combobox2 first.
Then, in conditional formatting, I tried 'Expression is' Not Null (did not work), Not "" (again did not work).
What is the right rule for this?

[CJ_London]

you need something like

Expression is...not isnull(comboa) or not isnull(combob)

for combo2 - should be no need to disable it first

[Bradex]

1)

you need something like

Expression is...not isnull(comboa) or not isnull(combob)

It is not working. I think I am doing something wrong. It looks like this [combo1]=Not IsNull([combo1]"a") Or Not IsNull([combo1]"b")


2)

for combo2 - should be no need to disable it first

I don't understand. If combo2 is not disabled in the first place, how can the expression enable it?

3) What is surprising to me is that even the 'Or' does not work. e.g. [combo1]="a" Or "b" Or "c"

[ssanfu]

Interesting... I would have just used VBA to set the Enabled property.

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Cannot have this....

[combo1]=Not IsNull([combo1]"a") Or Not IsNull([combo1]"b")

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This is close but won't work. You have to explicitly compare the values to a control.

[combo1]="a" Or "b" Or "c"

like this:

[combo1]="A" Or [combo1]="B" Or [combo1]="C"

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I did get this to work: In Combo2, set CF to
Expression is...

[combo1] Is Null Or ([combo1]<>"A" And [combo1]<>"B" And [combo1]<>"C")

This says:
If Combo1 is NULL OR Combo1 does not contain "A" or "B" or "C", then disable Combo2

Combo2 must be enabled


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If you only have "A", "B" and "C" (and Null) available in Combo1, then in CF for Combo2, you could just use

[combo1] Is Null

[Bradex]

Awesome!