自定义类序列化成xml，并获得xml内容

            

            using System.Xml.Serialization;
            //--序列化到XML

            MemoryStream s = new MemoryStream();
            XmlSerializer serializer = new XmlSerializer(sm.GetType());

　　　　//将类sm序列化到s中
            serializer.Serialize(s, sm);
           //依次读取s里的内容
             string inputString = System.Text.Encoding.Default.GetString(s.ToArray());