Iteration problem. Calling a function but crashes when eof reached

[tarenja]

I have a simple form that allows the user to loop through all records in a table.
On each iteration there are calls to a function.


The calls are being made from text boxes.
It all works fine until I get to the end of the table when an empty set of values is passed to the function and then it crashes.
I understand why it crashes but I'm don't know what approach to use to prevent it calling the function when the EOF is reached.
Can I keep using the "standard" MS Access navigation buttons on the form or do I need to set up my own iteration controls and somehow test for end of file on each iteration?
Any help would be greatly appreciated.

[pbaldy]

You should be able to modify your function to handle the empty values. Hard to be specific without seeing it, but likely you need to declare the input parameters as Variant and test them for Null in the function.

[tarenja]

As soon as the eof if reached the function goes to the error handler.
I have no idea of what to test for to trap the problem.

Public Function getActivityNames(DelegateID As Variant, ActivityIDs As Variant) As Variant

Dim strSql As String
Dim strOut As String
Dim Arrayids As Variant
Dim i As Integer
Dim ingLength As Integer
Dim dbs As DAO.Database
Dim rsB As DAO.Recordset
Dim rsC As DAO.Recordset

On Error GoTo Err_Handler

[tarenja]

Thank you. I tried:
Debug.Print DelegateID, ActivityIDs
DelegateID was null hence
If DelegateID <> Null Then
don't do anything

and bingo.

[tarenja]

I just read that my solution isn't technically correct.
I've now changed it to:
If IsNull(DelegateID) Then Exit Function

[pbaldy]

So it's working now?

[tarenja]

Yes thank you very much.
You pointed me in the right direction to look for the solution.

[pbaldy]

No problem.