var stream = new MemoryStream();
using (var fileStream = new FileStream(@"C:\Users\Robert\Desktop\hello.txt", FileMode.Open, FileAccess.Read))
{
    fileStream.CopyTo(stream);
}

var result = string.Empty;
stream.Position = 0;
using (var reader = new StreamReader(stream))
{
    result = reader.ReadToEnd();
}
	
MessageBox.Show(result.Length.ToString());



===========


[ServiceContract(CallbackContract=typeof(ISocketServiceCallback))]
    public interface ISocketService
    {
        [OperationContract(IsOneWay=true)]
        void Start();
    }

    public interface ISocketServiceCallback
    {
        [OperationContract(IsOneWay=true)]
        void Update(string message);
    }

    public class SocketService : ISocketService
    {
        public async void Start()
        {
 	        var client = OperationContext.Current.GetCallbackChannel<ISocketServiceCallback>();
            var rand = new Random();
            double ticker = 29;
            await Task.Factory.StartNew(() =>
                {
                    while (true)
                    {
                        client.Update(string.Format("MSFT: {0:C}", ticker));
                        ticker += rand.Next(-1,1)+rand.NextDouble();
                        Thread.Sleep(500);
                    }
                });
        }
    }


=======

static void Main(string[] args)
        {
            var responder = new Responder();
            var instance = new InstanceContext(responder);
            var client = new ServiceReference1.SocketServiceClient(instance);
            client.Start();
            Console.ReadLine();

        }

        class Responder : ServiceReference1.ISocketServiceCallback
        {
            public void Update(string message)
            {
                Console.WriteLine(message);
            }
        }