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comparison error


I am getting the 'Operator is not valid for type 'DBNull' and string "".'
error on the following line;

If (mydatatable.Ro ws.Item(I).Item ("Forenames" ) Is System.DBNull.V alue) Then
' 'I' is the loop variable from 0 To mydatatable.Row s.Count - 1.

Any ideas on what is the reason for this error?



Nov 20 '05 #1
2 1157
you may want to specify item().value. technically, if you return a column
named forenames then that "object" will have an instance...whic h is what it
looks like you're testing for. see if testing the column's value
helps...which is what i think you want anyway right?


"John" <jo**@nospam.in fovis.co.uk> wrote in message
news:eT******** ******@tk2msftn gp13.phx.gbl...
| Hi
| I am getting the 'Operator is not valid for type 'DBNull' and string "".'
| error on the following line;
| If (mydatatable.Ro ws.Item(I).Item ("Forenames" ) Is System.DBNull.V alue)
| ' 'I' is the loop variable from 0 To mydatatable.Row s.Count - 1.
| Any ideas on what is the reason for this error?
| Thanks
| Regards
Nov 20 '05 #2
Hi John,

When I see your datatable it looks to me if it has this dimension
- Rows
-- Items
--- Items
I tought it was
- Rows
-- Items

The item exist but can be empty therefore it is not IS but =

So I think it has to be someting as

mydatatable.row s(i)("Forenames ") = Dbnull.value

I hope this helps a little bit?

I am getting the 'Operator is not valid for type 'DBNull' and string "".'
error on the following line;

If (mydatatable.Ro ws.Item(I).Item ("Forenames" ) Is System.DBNull.V alue) Then ' 'I' is the loop variable from 0 To mydatatable.Row s.Count - 1.

Any ideas on what is the reason for this error?

Nov 20 '05 #3

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