mchsamples-wpf-.net/ModelViewWPF/XmlData/XmlDataManager.cs

using Model;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
using System.Runtime.Serialization;

namespace XmlData
{
    public class XmlDataManager : IDataManager
    {
        string xmlFile = "nounours.xml";

        public XmlDataManager()
        {
            var projDir = Path.Combine(Directory.GetParent(Directory.GetCurrentDirectory()).FullName, GetType().GetTypeInfo().Assembly.GetName().Name);
            var dir = Path.Combine(projDir.ToString(), "XML");
            Directory.SetCurrentDirectory(dir);
        }

        DataContractSerializer Serializer { get; set; } = new DataContractSerializer(typeof(List<Nounours>));

        public IEnumerable<Nounours> LesNounours
        {
            get
            {
                using (Stream s = File.OpenRead(xmlFile))
                {
                    lesNounours = Serializer.ReadObject(s) as List<Nounours>;
                }
                return lesNounours.AsReadOnly();
            }
        }
        private List<Nounours> lesNounours = new List<Nounours>();

        public void Add(Nounours nounours)
        {
            if (lesNounours.Contains(nounours)) return;
            lesNounours.Add(nounours);

            SaveChanges();
        }

        public void Remove(Nounours nounours)
        {
            lesNounours.Remove(nounours);

            SaveChanges();
        }

        public void Update(Nounours nounours)
        {
            if (!lesNounours.Contains(nounours)) return;
            lesNounours.Remove(nounours);
            lesNounours.Add(nounours);

            SaveChanges();
        }

        private void SaveChanges()
        {
            using (Stream s = File.Create(xmlFile))
            {
                Serializer.WriteObject(s, lesNounours);
            }
        }
    }
}