How to test for Null

[Karen Hagerman]

I am textbox.oldvalue to save the previous value in a textbox so I can have a history of edits to a record. If the record is, however, a new record, the Null value of .oldvalue is generating runtime errors:

The following If-Then-Else comes up with a runtime error of '94': Invalid use of Null

If txtName.Oldvalue = Null Then
NameOldValue = "New Record"
Else
NameOldValue = txtName.OldValue
End If

This other If-Then-Else comes up with a runtime error of '424': Object Required

If txtName.Oldvalue is Null Then
NameOldValue = "New Record"
Else
NameOldValue = txtName.OldValue
End If

How can I test for Null without generating a runtime error OR is there a better test to apply if it is a new record that is being populated? Any help will be appreciated.
Karen

 

[RobFMS]

Karen

Try: If IsNull(Me.txtName.Oldvalue) Then


--

Rob

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I am textbox.oldvalue to save the previous value in a textbox so I can have a history of edits to a record. If the record is, however, a new record, the Null value of .oldvalue is generating runtime errors:

The following If-Then-Else comes up with a runtime error of '94': Invalid use of Null

If txtName.Oldvalue = Null Then
NameOldValue = "New Record"
Else
NameOldValue = txtName.OldValue
End If

This other If-Then-Else comes up with a runtime error of '424': Object Required

If txtName.Oldvalue is Null Then
NameOldValue = "New Record"
Else
NameOldValue = txtName.OldValue
End If

How can I test for Null without generating a runtime error OR is there a better test to apply if it is a new record that is being populated? Any help will be appreciated.
Karen

 

[Karen Hagerman]

Thank you so much. I am still learning VBA and who would have thought? Works great, thanks again.

Karen

Karen

Try: If IsNull(Me.txtName.Oldvalue) Then


--

Rob

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Problems with your database? Need to upgrade your application?
Contact the FMS Professional Solutions Group: www.fmsinc.com/consulting

 

[Chris Strug]

Karen,

You may also find the "nz()" function useful. This tests for a null and
replaces it with the value of your choice.

Chris


Thank you so much. I am still learning VBA and who would have thought?
Works great, thanks again.

Karen

 

[Karen Hagerman]

That is very cool, I hadn't seen that particular function at all, thanks
very much.

Karen