System.Xml.XPathNodePointer.MoveToNextNamespace C# (CSharp) Method

        internal bool MoveToNextNamespace(XPathNamespaceScope namespaceScope)
        {
            RealFoliate();
            Debug.Assert(_parentOfNS != null);
            XmlNode node = _node;
            //first check within the same boundelement
            if (_column != null)
            {
                Debug.Assert(_column.Namespace == StrReservedXmlns);
                if (namespaceScope == XPathNamespaceScope.Local && _parentOfNS != _node) //already outside scope
                    return false;
                XmlBoundElement be = _node as XmlBoundElement;
                Debug.Assert(be != null);
                DataRow curRow = be.Row;
                Debug.Assert(curRow != null);
                DataColumn curCol = PreviousColumn(curRow, _column, true);
                while (curCol != null)
                {
                    if (curCol.Namespace == StrReservedXmlns)
                    {
                        MoveTo(be, curCol, false);
                        return true;
                    }
                    curCol = PreviousColumn(curRow, curCol, true);
                }
                //didn't find it in this loop
                if (namespaceScope == XPathNamespaceScope.Local)
                    return false;
                //try its ancesstor
                do
                {
                    node = node.ParentNode;
                } while (node != null && node.NodeType != XmlNodeType.Element);
            }
            else if (_node.NodeType == XmlNodeType.Attribute)
            {
                XmlAttribute attr = (XmlAttribute)(_node);
                Debug.Assert(attr != null);
                node = attr.OwnerElement;
                if (node == null)
                    return false;
                if (namespaceScope == XPathNamespaceScope.Local && _parentOfNS != node) //already outside scope
                    return false;
                if (MoveToNextNamespace((XmlBoundElement)node, null, attr))
                    return true;
                //didn't find it
                if (namespaceScope == XPathNamespaceScope.Local)
                    return false;
                do
                {
                    node = node.ParentNode;
                } while (node != null && node.NodeType != XmlNodeType.Element);
            }
            // till now, node should be the next accesstor (bound) element of the element parent of current namespace node (attribute or data column)
            while (node != null)
            {
                //try the namespace attributes from the same element
                XmlBoundElement be = node as XmlBoundElement;
                if (MoveToNextNamespace(be, null, null))
                    return true;
                //no more namespace attribute under the same element
                do
                {
                    node = node.ParentNode;
                } while (node != null && node.NodeType == XmlNodeType.Element);
            }
            //didn't find the next namespace, thus return
            if (namespaceScope == XPathNamespaceScope.All)
            {
                MoveTo(_doc._attrXml, null, false);
                return true;
            }
            return false;
        }