Collection was modified enumeration operation may not execute

[vladk]

Hi everyone,

How it would be possible to fix the exception in this procedure? Any help will be appreciated. Thank you!

   Public Sub LoadEmailAddress()

        Dim strRecipient As String
        Dim dicRecipients As New Dictionary(Of String, String)
        Dim dicCopyGroups As New Dictionary(Of String, clsGroup)
        Dim MyGroup As clsGroup

        Try

            For Each strGroup In gdicGroups.Keys

                dicRecipients.Clear()
    
                sqlReader = GetSqlReaderForEmailAddressesNew(gConn, gdicGroups(strGroup))

                While sqlReader.Read()
                    strRecipient = sqlReader("RecipientEmail").ToString

                    If strRecipient.Trim <> "" Then
                        If Not dicRecipients.ContainsKey(strRecipient) Then dicRecipients.Add(strRecipient, strRecipient)
                    End If
                   
                End While
                
                MyGroup = gdicGroups(strGroup)
                MyGroup.Recipients = dicRecipients

                '***** The next line throws the exception              
                dicCopyGroups.Add(strGroup, MyGroup)

            Next strGroup

            gdicGroups = dicCopyGroups

            sqlReader.Close()

        Catch ex As Exception
            MessageBox.Show(ex.Message & vbCr & ex.TargetSite.Name, "....", MessageBoxButtons.OK, MessageBoxIcon.Error)
        End Try

    End Sub

 

[vladk]

Found the cause: it was byref call to GetSqlReaderForEmailAddressesNew.

Thank you