System.Xml.DocumentXmlWriter.CloseWithAppendAttribute C# (CSharp) Method

        private void CloseWithAppendAttribute() {
            XmlElement elem = start as XmlElement;
            Debug.Assert(elem != null);
            XmlAttributeCollection attrs = elem.Attributes;
            for (int i = 0; i < fragment.Count; i++) {
                XmlAttribute attr = fragment[i] as XmlAttribute; 
                Debug.Assert(attr != null);
                int offset = attrs.FindNodeOffsetNS(attr);
                if (offset != -1
                    && ((XmlAttribute)attrs.Nodes[offset]).Specified) {
                    throw new XmlException(Res.Xml_DupAttributeName, attr.Prefix.Length == 0 ? attr.LocalName : string.Concat(attr.Prefix, ":", attr.LocalName));
                }
            }
            for (int i = 0; i < fragment.Count; i++) {
                XmlAttribute attr = fragment[i] as XmlAttribute; 
                Debug.Assert(attr != null);
                attrs.Append(attr);
            }
        }