[ServiceContract]
    public interface IDataItems
    {
        [OperationContract]
        Stream GetStreamedClients();
    }
 
    [DataContract(Name = "Client", Namespace = "")]  
    public class Client
    {
        string _Id = "";
        string _Name = "";
        string _Code = "";
 
        public Client()
        {
        }
 
        [DataMember]
        public string Id 
        { 
            get {return this._Id;}
            set {this._Id = value;}
        }
 
        [DataMember]
        public string Name 
        { 
            get {return this._Name;}
            set {this._Name = value;}
        }
 
        [DataMember]
        public string Code
        { 
            get {return this._Code;}
            set { this._Code = value; } 
        }
    }
 
    [CollectionDataContract(Name = "Clients", Namespace = "")]
    public class Clients : List<Client>
    {
    }
 

            Clients list = GetClientsData;
            MemoryStream _stream = new MemoryStream();
 
            XmlTextWriter xw2 = new XmlTextWriter("D://XmlSerializeResult.xml", Encoding.UTF8);
            xw2.Formatting = Formatting.Indented;
            XmlDictionaryWriter writer2 = XmlDictionaryWriter.CreateDictionaryWriter(xw2);
            DataContractSerializer ser2 = new DataContractSerializer(typeof(Clients));
            ser2.WriteObject(writer2, list);
            writer2.Close();
            xw2.Close();            
            
            
            XmlTextWriter xw = new XmlTextWriter(_stream, Encoding.UTF8);
            xw.Formatting = Formatting.Indented;
            XmlDictionaryWriter writer = XmlDictionaryWriter.CreateDictionaryWriter(xw);
            DataContractSerializer ser = new DataContractSerializer(typeof(Clients));
            ser.WriteObject(writer, list);
                        
            
            return _stream;
 

            DataItemsClient di = new DataItemsClient();
 
            Stream _stream = di.GetStreamedClients();
            
	    XmlReader dreader = XmlReader.Create(_stream);
            Clients cls = null;
            DataContractSerializer ser = new DataContractSerializer(typeof(Clients));
            cls = (Clients)ser.ReadObject(dreader);

            _stream.Seek(0, SeekOrigin.Begin);
            _stream.Position = 0;