Intermediate NullReferenceException when calling DataRow.EndEdit()

Hi there

I have got an application with the following cateristics:

* A datatable is populated with records from a database.
* A set intervals the database is checked for changed records,
and the corresponding DataRows in the DataTable is updated accordingly.
* Invoke is used at all times for the update to ensure that the update is done by the the thread that created the window handle.
* A DataView is connected to the DataTable.
* A GridControl (Xceed) is connected to the DataView (readonly)

The following is a snippet of the code used to update the DataRow:

private void updateRowFrom(DataRow row)
{
    try
    {
        DataRow mainRow = findRowFor(row);
        if (mainRow != null)
        {
            updateRow(mainRow, row);
        }
        else
        {
            DataTable dt = _gridView.Table;
            DataRow newRow = dt.NewRow();
            updateRow(newRow, row);
            dt.Rows.Add(newRow);
        }
    }
    catch(Exception ex)
    {
        log.Error("Error performing 'update row' operation.", ex);
    }
}

private void updateRow(DataRow row2update, DataRow newValues)
{
    row2update.BeginEdit();
    copyFields(newValues, row2update);
    row2update.EndEdit();
}

private void copyFields(DataRow fromRow, DataRow toRow)
{
    foreach (DataColumn col in fromRow.Table.Columns)
    {
        toRow[col.ColumnName] = fromRow[col.ColumnName];
    }
}

I have confirmed that the DataRows in copyFields contains the exact same columns.

Every once in a while (probably less then 1% of the time), the following exception is thrown when DataRow.EndEdit() is called:

2005-09-21 12:07:52,978 [ERROR] - Error performing 'update row' operation.
Exception: System.NullReferenceException

Source: System.Data
   at System.Data.DataTable.RecordStateChanged(Int32 record1, DataViewRowState oldState1, DataViewRowState newState1, Int32 record2, DataViewRowState oldState2, DataViewRowState newState2)
   at System.Data.DataTable.SetNewRecord(DataRow row, Int32 proposedRecord, DataRowAction action, Boolean isInMerge)
   at System.Data.DataRow.EndEdit()
   at
eAirports.AODB.TrackingMerge.BO.TrackingGridManager.updateRowFrom(DataRow
row)

I have done a search on the web and it seems that some other developers have come up with the same error, but nobody published a solution. The following two patches have also apparently been tried with no success:

http://support.microsoft.com/ id=836874
http://support.microsoft.com/ id=889531

If there are any fixes or workaround for this issue, or if somebody could point me in the right direction it would be greatly appreciated.

Regards,

Charl

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