c# 读写xml

  /*
             <?xml version="1.0" encoding="gbk"?>
                <App>
                  <A>
                     <Op>61</Op>
                     <Serial>111111111111</Serial>
                     <Depart>210100010152</Depart>
                     <Section>003650</Section>
                     <type>0</type>
                </A>
               </App>
              */
            MemoryStream w = new MemoryStream(1000);
            XmlTextWriter writer = new XmlTextWriter(w, Encoding.GetEncoding("gb18030"))
            {
                Formatting = Formatting.Indented
            };
            writer.WriteStartDocument(false);
            writer.WriteStartElement("App");
            {
                writer.WriteStartElement("A");
                {
                    writer.WriteElementString("Op", "61");
                    writer.WriteElementString("Serial", "111111111111");
                    writer.WriteElementString("Depart", "210100010152");
                    writer.WriteElementString("Section", "003650");
                    writer.WriteElementString("type", "0");
                }
                writer.WriteEndElement();
            }
            writer.WriteEndElement();
            writer.Flush();
            Console.WriteLine(Encoding.GetEncoding("gb18030").GetString(w.GetBuffer()).Trim());