Deserializacja Xml, format odczytu.

private void MainForm_Load(object sender, EventArgs e)
        {
            XMLCust customer = new XMLCust();
            customer = (XMLCust)XMLObj.Load(customer, null, XMLName, null);
            this.tBCust.Text = customer.CustName;
        }
        private void MainForm_FormClosed(object sender, FormClosedEventArgs e)
        {
            XMLCust customer = new XMLCust();
            customer.CustName = this.tBCust.Text;
            XMLObj.Save(customer, null, XMLName, null);
            MessageBox.Show("Dane zostały zapisane do pliku .Xml!");
        } 

 public class XMLCust
    {
        public string CustName { get; set; }
        public XMLCust() { }
        public XMLCust(string Name)
        {
            CustName = Name;
        }
    }

 class XMLObj
    {
        private XMLObj()
        {}

        public static Object Load(Object serializableObject, Type[] extraTypes, string path, IsolatedStorageFile isolatedStorageFolder)
        {
            using (TextReader textReader = CreateTextReader(isolatedStorageFolder, path))
            {
                XmlSerializer xmlSerializer = CreateXmlSerializer(serializableObject, extraTypes);
                serializableObject = xmlSerializer.Deserialize(textReader);
            }
            return serializableObject;
        }

        public static void Save(Object serializableObject, Type[] extraTypes, string path, IsolatedStorageFile isolatedStorageFolder)
        {
            using (TextWriter textWriter = CreateTextWriter(isolatedStorageFolder, path))
            {
                XmlSerializer xmlSerializer = CreateXmlSerializer(serializableObject, extraTypes);
                xmlSerializer.Serialize(textWriter, serializableObject);
            }
        }

        private static TextReader CreateTextReader(IsolatedStorageFile isolatedStorageFolder, string path)
        {
            TextReader textReader = null;
            if (isolatedStorageFolder == null)
                textReader = new StreamReader(path);
            else
                textReader = new StreamReader(new IsolatedStorageFileStream(path, FileMode.Open, isolatedStorageFolder));
            return textReader;
        }

        private static TextWriter CreateTextWriter(IsolatedStorageFile isolatedStorageFolder, string path)
        {
            TextWriter textWriter = null;
            if (isolatedStorageFolder == null)
                textWriter = new StreamWriter(path);
            else
                textWriter = new StreamWriter(new IsolatedStorageFileStream(path, FileMode.OpenOrCreate, isolatedStorageFolder));
            return textWriter;
        }

        private static XmlSerializer CreateXmlSerializer(Object serializableObject, System.Type[] extraTypes)
        {
            Type ObjectType = serializableObject.GetType();
            XmlSerializer xmlSerializer = null;
            if (extraTypes != null)
                xmlSerializer = new XmlSerializer(ObjectType, extraTypes);
            else
                xmlSerializer = new XmlSerializer(ObjectType);
            return xmlSerializer;
        }
    }

new StreamReader(path, Encoding.UTF8);

new StreamWriter(path, Encoding.UTF8);

textWriter = new StreamWriter(path, Encoding.UTF8);