issue with DLOOKUP syntax error for new database

Question

I have a database with 4 tables but primarily it is a diversion table/form (DiversionT/F) and a payback table/form (PaybackT/F). Basically, when my program loans parts to other programs in my organization a diversion is created in DiversionT. When the program want to payback they create a payback entry in PaybackT.

I have an issue that I am confused about: On PaybackF the user enters an NSN (long part code) that they want to payback. Ultimately, I want some of the form to auto populate with part info based on the NSN entered. The info is stored in DiversionT. I have created a few text boxes on PaybackF to show the info. The first text box I am trying to autofill based on the NSN is a textbox called PartName. It should search DiversionT for that NSN and fill in the appropriate PartName on PaybackF. In the control Source for the box I typed:

=DLookUp("[PartName]","[DiversionT]", "[PartName]=" & Forms![PaybackF]!NSN)

I get the following error:

The expression you entered contains invalid syntax.

To be perfectly honest I don't really understand VBA yet (spent my life until now with C, C++, Java, and Python) but looked up the function on the Microsoft site.

If I am not going about this right, please also let me know?

Answer 1

You can't enter VBA in to form properties like source control. VBA is only used in procedural code in the VBE. That being said, there is a DLOOKUP function available to form fields and the syntax is similar. This is a cause of your confusion.

EXAMPLE SYNTAX FOR NUMBERS:

=DLookUp("[PartName]","DiversionT", "[PartName]=" & [NSN])

EXAMPLE SYNTAX FOR STRINGS:

=DLookUp("[PartName]","DiversionT", "[PartName]='" & [NSN] & "'")

NOTE: I can't tell what form you are on or if NSN is from a parent form or subform. Basically, NSN needs to be readable from the same form where that text field exists.

Answer 2

When using DLookup to get data, if you are dealing with text strings, you need to ensure that you use single quotes to wrap the text in.

Also, I think that your logic in the DLookup is slightly wrong. I think that this is what you are after:

=DLookUp("[PartName]","[DiversionT]", "[NSN]='" & Me!NSN & "'")

Regards,