System.Net.Sockets.TcpListener.EndAcceptTcpClient C# (CSharp) Méthode

        public TcpClient EndAcceptTcpClient(IAsyncResult asyncResult)
        {
            if (NetEventSource.IsEnabled) NetEventSource.Enter(this);

            if (asyncResult == null)
            {
                throw new ArgumentNullException(nameof(asyncResult));
            }

            LazyAsyncResult lazyResult = asyncResult as LazyAsyncResult;
            Socket asyncSocket = lazyResult == null ? null : lazyResult.AsyncObject as Socket;
            if (asyncSocket == null)
            {
                throw new ArgumentException(SR.net_io_invalidasyncresult, nameof(asyncResult));
            }

            // This will throw ObjectDisposedException if Stop() has been called.
            Socket socket = asyncSocket.EndAccept(asyncResult);
            if (NetEventSource.IsEnabled) NetEventSource.Exit(this, socket);
            return new TcpClient(socket);
        }

        public static void Main(string[] args)
        {
            Action<object> cw = Console.WriteLine;
              cw("* any");
              cw(IPAddress.Any);
              cw(IPAddress.IPv6Any);
              cw("* loopback");
              cw(IPAddress.Loopback);
              cw(IPAddress.IPv6Loopback);
              cw("* none");
              cw(IPAddress.None);
              cw(IPAddress.IPv6None);
              cw("* bc4"); //trivia: there is no bc6, only multicast
              cw(IPAddress.Broadcast);

              TcpListener l = new TcpListener(IPAddress.Any, 7896);
              l.Start();
              l.BeginAcceptTcpClient(ar => {
            var c = l.EndAcceptTcpClient(ar);
            l.Stop();
            //var s = new StreamWriter(c.GetStream());
            //s.WriteLine("test writer : needed");
            //s.Flush();
            var bs = System.Text.Encoding.UTF8.GetBytes("test direct : not needed");
            c.GetStream().Write(bs, 0, bs.Length);
            c.Close();
              }, l);

              //start client
              var q = new TcpClient("localhost", 7896);
              var qs = new StreamReader(q.GetStream());
              Console.WriteLine(qs.ReadLine());
              // l.Stop();
        }