[02/03] Collection was modified; enumeration operation may not execute.

Hi
I got 2 datagrid and single column. Datagrid 1 contains 2 rows number 2 and 3. Datagrid2 contains 1, 2 and 3. I want to remove the duplicate numbers on datagrid2. The tables are unrelated so i would have to use cursors.

VB Code:

Try
            Dim a As String
            For i As Integer = 0 To ds1.Tables(0).Rows.Count - 1
                a = Me.DataGrid1.Item(i, 0).ToString.TrimEnd
                For Each row As DataRow In ds2.Tables(0).Rows
                    ''Console.WriteLine(row.Item(0).ToString)
 
                    If row.Item(0).ToString = a Then
 
                        ds2.Tables(0).Rows.Remove(row)
                    End If
                Next
            Next
        Catch ex As Exception
            Console.WriteLine(ex.Message)
        End Try
        Me.DataGrid2.DataSource = ds2.Tables(0)

I get the exception Collection was modified; enumeration operation may not execute. Any suggestions , thanks.
Jorge

I would suggest you need to iterate through the rows backwards, as you are removing columns and that will change the boundries of your For Each Rows loop.

ie

Instead of

VB Code:

For Each row As DataRow In ds2.Tables(0).Rows
                    ''Console.WriteLine(row.Item(0).ToString)
 
                    If row.Item(0).ToString = a Then
 
                        ds2.Tables(0).Rows.Remove(row)
                    End If
                Next

Use

VB Code:

For intRow As Integer =  ds2.Tables(0).Rows.Count - 1 to 0 Step - 1
   Next