如何为 Windows Phone 创建和使用 UDP 套接字客户端应用程序

原文地址：http://msdn.microsoft.com/zh-cn/library/hh202864(v=vs.92).aspx

/// <summary>        /// Send the given data to the server using the established connection        /// </summary>        /// <param name="serverName">The name of the server</param>        /// <param name="portNumber">The number of the port over which to send the data</param>        /// <param name="data">The data to send to the server</param>        /// <returns>The result of the Send request</returns>        public string Send(string serverName, int portNumber, string data)        {            string response = "Operation Timeout";            // We are re-using the _socket object that was initialized in the Connect method            if (_socket != null)            {                // Create SocketAsyncEventArgs context object                SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();                // Set properties on context object                socketEventArg.RemoteEndPoint = new DnsEndPoint(serverName, portNumber);                // Inline event handler for the Completed event.                // Note: This event handler was implemented inline in order to make this method self-contained.                socketEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(delegate(object s, SocketAsyncEventArgs e)                {                    response = e.SocketError.ToString();                    // Unblock the UI thread                    _clientDone.Set();                });                // Add the data to be sent into the buffer                byte[] payload = Encoding.UTF8.GetBytes(data);                socketEventArg.SetBuffer(payload, 0, payload.Length);                // Sets the state of the event to nonsignaled, causing threads to block                _clientDone.Reset();                // Make an asynchronous Send request over the socket                _socket.SendToAsync(socketEventArg);                // Block the UI thread for a maximum of TIMEOUT_MILLISECONDS milliseconds.                // If no response comes back within this time then proceed                _clientDone.WaitOne(TIMEOUT_MILLISECONDS);            }            else            {                response = "Socket is not initialized";            }            return response;        }

/// <summary>        /// Receive data from the server        /// </summary>        /// <param name="portNumber">The port on which to receive data</param>        /// <returns>The data received from the server</returns>        public string Receive(int portNumber)        {            string response = "Operation Timeout";            // We are receiving over an established socket connection            if (_socket != null)            {                // Create SocketAsyncEventArgs context object                SocketAsyncEventArgs socketEventArg = new SocketAsyncEventArgs();                socketEventArg.RemoteEndPoint = new IPEndPoint(IPAddress.Any, portNumber);                // Setup the buffer to receive the data                socketEventArg.SetBuffer(new Byte[MAX_BUFFER_SIZE], 0, MAX_BUFFER_SIZE);                // Inline event handler for the Completed event.                // Note: This even handler was implemented inline in order to make this method self-contained.                socketEventArg.Completed += new EventHandler<SocketAsyncEventArgs>(delegate(object s, SocketAsyncEventArgs e)                {                    if (e.SocketError == SocketError.Success)                    {                        // Retrieve the data from the buffer                        response = Encoding.UTF8.GetString(e.Buffer, e.Offset, e.BytesTransferred);                        response = response.Trim('\0');                    }                    else                    {                        response = e.SocketError.ToString();                    }                    _clientDone.Set();                });                // Sets the state of the event to nonsignaled, causing threads to block                _clientDone.Reset();                // Make an asynchronous Receive request over the socket                _socket.ReceiveFromAsync(socketEventArg);                // Block the UI thread for a maximum of TIMEOUT_MILLISECONDS milliseconds.                // If no response comes back within this time then proceed                _clientDone.WaitOne(TIMEOUT_MILLISECONDS);            }            else            {                response = "Socket is not initialized";            }            return response;        }        /// <summary>        /// Closes the Socket connection and releases all associated resources        /// </summary>        public void Close()        {            if (_socket != null)            {                _socket.Close();            }        }