using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Xml;

namespace ConsoleApp1
{
    class Program
    {
        public const String xmlPath = "info.xml";

        static void Main(string[] args)
        {

            IDictionary<String, List<String>> infos = new Dictionary<String, List<String>>();

            infos.Add("Evan", new List<string>() { "123", "456" });

            SaveXML(infos);

            ReadXML();
            Console.ReadKey();
        }

        public static void SaveXML(IDictionary<String, List<String>> infos)
        {
            if (infos == null || infos.Count == 0)
            {
                return;
            }

            XmlDocument xmlDoc = new XmlDocument();

            XmlDeclaration dec = xmlDoc.CreateXmlDeclaration("1.0", "utf-8", null);

            xmlDoc.AppendChild(dec);

            XmlElement _infos = xmlDoc.CreateElement("infos");

            foreach (KeyValuePair<String, List<String>> item in infos)
            {
                XmlElement info = xmlDoc.CreateElement("info");

                XmlElement name = xmlDoc.CreateElement("file1");
                name.InnerText = item.Key;

                info.AppendChild(name);

                XmlNode filelist = xmlDoc.CreateElement("filelist");

                info.AppendChild(filelist);

                foreach (String number in item.Value)
                {
                    XmlElement filed = xmlDoc.CreateElement("filed");
                    filed.InnerText = number;

                    filelist.AppendChild(filed);
                }

                _infos.AppendChild(info);
            }

            xmlDoc.AppendChild(_infos);

            xmlDoc.Save(xmlPath);
        }

        public static IDictionary<String, List<String>> ReadXML()
        {
            IDictionary<String, List<String>> infos = new Dictionary<String, List<String>>();

            if (File.Exists(xmlPath))
            {
                XmlDocument xmlDoc = new XmlDocument();

                xmlDoc.Load(xmlPath);

                XmlNode xn = xmlDoc.SelectSingleNode("infos");

                XmlNodeList xnl = xn.ChildNodes;

                foreach (XmlNode xnf in xnl)
                {
                    XmlElement xe = (XmlElement)xnf;

                    XmlNode nameNode = xe.SelectSingleNode("file1");

                    string name = nameNode.InnerText;
                    Console.WriteLine(name);
                    XmlNode filelist = xe.SelectSingleNode("filelist");

                    List<String> list = new List<string>();

                    foreach (XmlNode item in filelist.ChildNodes)
                    {
                        list.Add(item.InnerText);
                    }

                    infos.Add(name, list);
                }
            }

            return infos;
        }
    }
}