using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Collections;using System.Configuration;using System.Xml;namespace CustomConfig{    public class MailServerConfigHandler:IConfigurationSectionHandler    {        public object Create(object parent, object configContext, System.Xml.XmlNode section)        {            MailServerConfig config = new MailServerConfig();            config.Provider = section.Attributes["provider"] == null ? "" : section.Attributes["provider"].Value;            foreach (XmlNode child in section.ChildNodes)            {                MailServer server = new MailServer();                server.Client = child.Attributes["client"] == null ? "" : child.Attributes["client"].Value;                foreach (XmlNode grandChild in child.ChildNodes)                {                    server.ServerNode.Add(grandChild.Name, grandChild.InnerText);                }                config.Add(server);            }            return config;        }    }    public class MailServer    {        private Hashtable serverNode;        public MailServer()        {            serverNode = new Hashtable();        }        public Hashtable ServerNode        {            get { return serverNode; }        }        public string Client { get; set; }        public string Address        {            get { return serverNode["address"] as string; }        }        public string UserName        {            get { return serverNode["username"] as string; }        }        public string Password        {            get { return serverNode["password"] as string; }        }    }    public class MailServerConfig : List<MailServer>    {        public string Provider { get; set; }    }}

<?xml version="1.0" encoding="utf-8" ?><configuration>  <configSections>    <section name="mailServerGroup" type="CustomConfig.MailServerConfigHandler,CustomConfig"/>  </configSections>  <mailServerGroup provider="www.edong.com">    <mailServer client="forum.tracefact.net">      <address>addr1</address>      <userName>user1</userName>      <password>pwd1</password>    </mailServer>        <mailServer client="blog.tracefact.com">      <address>addr2</address>      <userName>user2</userName>      <password>pwd2</password>    </mailServer>  </mailServerGroup></configuration>

using System;using System.Collections.Generic;using System.Linq;using System.Text;using CustomConfig;using System.Configuration;namespace ConsoleApplication1{    class Program    {        static void Main(string[] args)        {            example();        }        private static void example()        {            MailServerConfig serverGroup = (MailServerConfig)ConfigurationManager.GetSection("mailServerGroup");            Console.WriteLine("provider:\t"+serverGroup.Provider);            foreach (MailServer config in serverGroup)            {                Console.WriteLine("-------------------------------");                Console.WriteLine("client:\t"+config.Client);                Console.WriteLine("address:\t"+config.Address);                Console.WriteLine("userName:\t"+config.UserName);                Console.WriteLine("password:\t"+config.Password);            }            Console.ReadKey();        }    }}