System.Xml.XmlDataDocument.OnNestedParentChange C# (CSharp) Méthode

        private void OnNestedParentChange(DataRow child, XmlBoundElement childElement, DataColumn childCol)
        {
            Debug.Assert(child.Element == childElement && childElement.Row == child);
            // This function is (and s/b) called as a result of ROM changes, therefore XML changes done here should not be sync-ed to ROM
            Debug.Assert(_ignoreXmlEvents == true);
#if DEBUG
            // In order to check that this move does not change the connected/disconnected state of the node
            bool fChildElementConnected = IsConnected(childElement);
#endif
            DataRow parentRowInTree;
            if (childElement == DocumentElement || childElement.ParentNode == null)
                parentRowInTree = null;
            else
                parentRowInTree = GetRowFromElement((XmlElement)childElement.ParentNode);
            DataRow parentRowInRelation = GetNestedParent(child);

            if (parentRowInTree != parentRowInRelation)
            {
                if (parentRowInRelation != null)
                {
                    XmlElement newParent = GetElementFromRow(parentRowInRelation);
                    newParent.AppendChild(childElement);
                }
                else
                {
                    // no parent? Maybe the parentRow is during changing or childCol is the ID is set to null ( detached from the parent row ).
                    DataRelation relation = GetNestedParentRelation(child);
                    if (childCol == null || relation == null || Convert.IsDBNull(child[childCol]))
                    {
                        EnsureNonRowDocumentElement().AppendChild(childElement);
                    }
                    else
                    {
                        DataColumn colInParent = FindAssociatedParentColumn(relation, childCol);
                        Debug.Assert(colInParent != null);
                        object comparedValue = colInParent.ConvertValue(child[childCol]);
                        if (parentRowInTree._tempRecord != -1 && colInParent.CompareValueTo(parentRowInTree._tempRecord, comparedValue) != 0)
                        {
                            EnsureNonRowDocumentElement().AppendChild(childElement);
                        }
                        //else do nothing because its original parentRowInRelation will be changed so that this row will still be its child
                    }
                }
            }
#if DEBUG
            // We should not have changed the connected/disconnected state of the node (since the row state did not change) -- IOW if the original childElem was in dis-connected
            // state and corresponded to a detached/deleted row, by adding it to the main tree we become inconsistent (since we have now a deleted/detached row in the main tree)
            // Same goes when we remove a node from connected tree to make it a child of a row-node corresponding to a non-live row.
            Debug.Assert(fChildElementConnected == IsConnected(childElement));
            Debug.Assert(IsRowLive(child) ? IsConnected(childElement) : !IsConnected(childElement));
#endif
        }