Removing rows from datatable + AcceptChanges

Question

Hi everybody,

I have 2 datatables in my ASP.NET application. I loop though both of them, and if I find a match, I delete that particular row from the outer datatable, lik so:

For i As Integer = 0 To dtFixedActs.Count - 1
        For j As Integer = 0 To dtTotals.Count - 1                
            If dtFixedActs.Rows(i).Item("Activity") = dtTotals.Rows(j).Item("Activity") Then
                dtFixedActs.Rows(i).Delete()
                i += 1
                j += 1
            End If
        Next            
        dtFixedActs.AcceptChanges()
    Next

This works fine, except when the dtFixedActs contains only 1 row and a match is found in the other datatable. I get an "there is no row at position 1" error. This makes sense because with i+=1 I want to get to the next row, which is not possible in this case.

I have tried to move around the dtFixedActs.AcceptChanges command in and out of the 1st loop but to no avail. I also commented out the i+=1 line, but then I get the "Deleted row information cannot be accessed through the row." error.

I don't know how to program around this issue. When dtFixedActs contains more than 1 row, the problem does not occur.

Any suggestions? Thanks in advance!

Answer 1

you will have a problem if a match is found dfFixedActs(dtFixedActs.Count - 1), because i increase to out side boundary. just added a condition to prevent i or j move out of the boundary, such as i <= dtFixedActs.Count - 1 and j <= dtTotals.Count - 1 .

Answer 2

Strangest thing, I seem to have solved the issue. I added a try catch exception code block like so:

For i As Integer = 0 To dtFixedActs.Count - 1
        For j As Integer = 0 To dtTotals.Count - 1                
            Try
                If dtFixedActs.Rows(i).Item("Activity") = dtTotals.Rows(j).Item("Activity") Then
                    dtFixedActs.Rows(i).Delete()
                    i += 1
                    j += 1
                End If
            Catch ex As Exception

            End Try

        Next
        dtFixedActs.AcceptChanges()
    Next

Everything seems to work fine now. Does anyone have an explanation for this, as I doubt that this is a valid solution?