直接上代码

using System.Diagnostics;
using System.Text;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.IO;
using System.Text.RegularExpressions;
using System.Dynamic;
namespace ConsoleApplication7
{
    public class Test
    {
        public TestDy TestDy { get; set; }
    }
    public class TestDy : DynamicObject, IXmlSerializable
    {
        public override bool TryGetMember(GetMemberBinder binder, out object result)
        {
            string name = binder.Name.ToLower();
            bool exist = Dict.TryGetValue(name, out result);
            if (!exist)
            {
                // 不存在,默认空
                result = null;
            }
            return true;
        }
        public override bool TrySetMember(SetMemberBinder binder, object value)
        {
            Dict[binder.Name.ToLower()] = value;
            return true;
        }
         Dictionary<string, object> Dict = new Dictionary<string, object>();
        public string Sid { get; set; }
        public XmlSchema GetSchema()
        {
            return (null);
        }
        public void ReadXml(XmlReader reader)
        {
            Sid = reader.ReadString();
        }
        public void WriteXml(XmlWriter writer)
        {
            writer.WriteStartElement("Sid");
            writer.WriteAttributeString("id", Sid.ToString());
            foreach (var item in Dict)
            {
                writer.WriteAttributeString(item.Key, item.Value.ToString());
            }
            writer.WriteEndElement();
        }
    }
    public class XML
    {
        public static string XmlSerialize(Type type, object obj)
        {
            MemoryStream Stream = new MemoryStream();
            XmlSerializer xml = new XmlSerializer(type);
            try
            {
                xml.Serialize(Stream, obj);
            }
            catch (InvalidOperationException)
            {
                throw;
            }
            Stream.Position = 0;
            StreamReader sr = new StreamReader(Stream);
            string str = sr.ReadToEnd();
            sr.Dispose();
            Stream.Dispose();
            return str;
        }
        public static string SerializeXml(object value)
        {
            XmlSerializer serializer = new XmlSerializer(value.GetType());
            using (MemoryStream ms = new MemoryStream())
            {
                serializer.Serialize(ms, value);
                ms.Seek(0, SeekOrigin.Begin);
                using (StreamReader sr = new StreamReader(ms))
                {
                    return sr.ReadToEnd();
                }
            }
        }
        public static string XmlSerialize<T>(T obj)
        {
            XmlSerializer serializer = new XmlSerializer(typeof(T));
            MemoryStream mem = new MemoryStream();
            XmlTextWriter writer = new XmlTextWriter(mem, Encoding.UTF8);
            XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
            ns.Add("", "");
            serializer.Serialize(writer, obj, ns);
            writer.Close();
            return Encoding.UTF8.GetString(mem.ToArray());
        }
    }
    public class Program
    {
        static void Main(string[] args)
        {
            var test = new Test();
            dynamic dy = new TestDy();
            test.TestDy = dy;
            //dynamic dy = new TestDy();
            dy.Sid = "9527";
            dy.属性1 = "123";
            dy.属性2 = "456";
            dy.属性3 ="789";
            TextWriter writer = new StreamWriter("C:\\Users\\LYY\\Desktop\\Test.xml");
            //string strxml = XML.XmlSerialize(test);
            //string strxml = XML.XmlSerialize<Test>(test);           
            //writer.WriteLine(strxml);
            XmlSerializer serializer = new XmlSerializer(test.GetType());
            serializer.Serialize(writer,test);
            writer.Close();
        }
    }
}