Threading a Synchronous XNA Network - c#

I have been doing several hours of research on a topic that I thought would've been very trivial. So far I've come up empty handed and wanted to see what you guys think. I'm currently messing with XNA (which is actually quite irrelevant now that I think about it) building a client/server architecture for a "game" project. Really nothing more than playing around with networking, animations, etc.
Anyway I've read quite a bit about the differences between Synchronous and Asynchronous networks and the viability of threading synchronous applications to simulate asynchronous behavior and have decided to do just that. Now I know my code isn't pretty but I'm just testing right now. Here's how it's (sort of) set up:
Game is run in the main thread.
On initialization->Connect to server.
Send x position of player class's sprite object to server.
Server receives, acknowledges with a print to console and sends the same data back.
Data is read into a logfile.
I've begun work on a messenger class that will eventually read (or sniff) the packets coming from the server and dispatch them accordingly making draw/update calls as needed. My problem is that I cant figure out how to properly thread the connection method to have that run (and then block?) separate from the Send/Receive loop (or what I'd like to be a continuous loop).
Like I said I'm no expert, I'm just doing this for fun so I may be all over the place. Anyway here are the essentials code-wise:
Networking.cs
using System;
using System.Net;
using System.Net.Sockets;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Threading;
namespace DrawTest
{
class Networking
{
public void StartClient(Messenger m)
{
// Data buffer for incoming data.
StreamWriter _con = new StreamWriter("data.txt");
// Connect to a remote device.
try {
// Establish the remote endpoint for the socket.
// This example uses port 11000 on the local computer.
IPHostEntry ipHostInfo = Dns.Resolve("127.0.0.1");
IPAddress ipAddress = ipHostInfo.AddressList[0];
IPEndPoint remoteEP = new IPEndPoint(ipAddress,3000);
// Create a TCP/IP socket.
Socket sender = new Socket(AddressFamily.InterNetwork,
SocketType.Stream, ProtocolType.Tcp );
// Connect the socket to the remote endpoint. Catch any errors.
try {
sender.Connect(remoteEP);
_con.WriteLine("Socket connected to {0}",
sender.RemoteEndPoint.ToString());
while (m.isAlive)
{
m.SocketStream(sender, _con);
}
if (Messenger.mPacket() == "close_socket")
{
_con.WriteLine("Connection closed by client.");
sender.Shutdown(SocketShutdown.Both);
sender.Close();
}
} catch (ArgumentNullException ane) {
_con.WriteLine("ArgumentNullException : {0}",ane.ToString());
} catch (SocketException se) {
_con.WriteLine("SocketException : {0}",se.ToString());
} catch (Exception e) {
_con.WriteLine("Unexpected exception : {0}", e.ToString());
}
_con.Flush();
}
catch (Exception e) {
_con.WriteLine(e.ToString());
_con.Flush();
}
}
}
}
Messenger.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.IO;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework;
namespace DrawTest
{
public class Messenger
{
byte[] bytes = new byte[1024];
byte[] incBuffer = new byte[1024];
public bool isAlive = true;
Vector2 position = new Vector2(0.0f, 0.0f);
public Vector2 getPos()
{
return position;
}
public void setPos(Vector2 pos)
{
position = pos;
}
public void SocketStream(Socket s, StreamWriter logfile)
{
byte[] msg = null;
int bytesSent = 0;
int bytesRec = 0;
msg = BitConverter.GetBytes(position.X);
// Encode the data string into a byte array.
bytesSent = s.Send(msg);
// Receive the response from the remote device.
bytesRec = s.Receive(incBuffer);
//logfile.WriteLine(Messenger.mDecoder(incBuffer, bytesRec));
}
public string mDecoder(byte[] msg, int size)
{
string DecodedMessage;
byte[] bytes = new byte[1024];
DecodedMessage = Encoding.ASCII.GetString(msg, 0, size);
if (DecodedMessage == "close_socket")
{
isAlive = false;
return DecodedMessage;
}
return DecodedMessage;
}
public static string mPacket()
{
return null;
}
}
}
Think that should do it. The other code is relatively self-explanatory (abstract player/sprite classes and the typical XNA Game.cs)
Thanks in advance for any help!

You may do something along the lines of:
public void SendData(Socket s)
{
byte[] msg = null;
int bytesSent = 0;
msg = BitConverter.GetBytes(position.X);
// Encode the data string into a byte array.
bytesSent = s.Send(msg);
}
void ReceiveData(Socket s)
{
int bytesExpected = 1024; // somehow specify the number of bytes expected
int totalBytesRec = 0; // adds up all the bytes received
int bytesRec = -1; // zero means that you're done receiving
while(bytesRec != 0 && totalBytesRec < bytesExpected )
{
// Receive the response from the remote device.
bytesRec = s.Receive(incBuffer);
totalBytesRec += bytesRec;
}
}
Back in your StartClient class, you should start your receive thread first then send the data:
// Start your receive thread first
Thread t = new Thread(()=>{ReceiveData(sender);});
t.IsBackground = true;
t.Start();
// Then send the data
SendData(sender);
// Wait for the thread to terminate (if you need to)
t.Join(30000);
// Once you close the socket, then it will throw an exception
// in the receive thread (which you should catch) and you can
// exit the thread, thus terminating the thread.
This is roughly how you would start a thread that performs the receive.
Update (based on comments)
I would recommend that you take a look at some of the Patterns for Multithreaded Network Server in C#.
The server side should start a new thread for every client connection accepted and a "connection handler" should take over and manage the sending/receiving of data from there on:
while(serverRunning)
{
Socket clientSocket = serverSocket.Accept();
// You can write your own connection handler class that automatically
// starts a new ReceiveData thread when it gets a client connection
ConnectionHandler chandler = new ConnectionHandler(clientSocket);
// Have an on-client-disconnected event which you can subscribe to
// and remove the handler from your list when the client is disconnected
chandler.OnClinetDisconnectedEvent += new OnClientDisconnectedDelegate(OnClientDisconnected);
mHandlerList.Add(chandler);
}
// When you're terminating the program, then just go through
// the list of active ConnectionHandlers and call some method
// which tells them to close their connections with the clients
// and terminates the thread.
To be even more precise, you are likely to have the very similar behavior with the client's and the server's ReceiveData method: i.e. synchronously send a message back whenever they receive some message. Here is a more realistic example that might help you conceptualize it better:
void ReceiveData(Socket s)
{
int bytesExpected = 1024; // somehow specify the number of bytes expected
int totalBytesRec = 0; // adds up all the bytes received
int bytesRec = -1; // zero means that you're done receiving
while(bytesRec != 0 && totalBytesRec < bytesExpected )
{
// Receive the response from the remote device.
bytesRec = s.Receive(incBuffer);
totalBytesRec += bytesRec;
if(needToReply)
{
// Send another message
SendData(s);
}
}
}
This is a long running thread, of course, so you would generally like to have it run for as long as the player is connected to the internet. The comment about closing the connection and terminating the thread is specifically for the situation where you need to have a graceful exit (i.e. the player quits the game or the rare case that server needs to be shut down).

Related

How to communicate between two Unity apps with TCP?

Update
I figured out what the problem was. I was trying to move too much data over TCP, and it was causing freeze-ups. For some reason, this wasn't manifesting in the editor...who knows for what reason. If anyone else stumbles upon this problem (in a program like Unity, where functions are looping constantly and data is always being processed), consider that you're moving too much irrelevant data.
Original Post
I've run into quite the problem, and I'm hoping I can receive some guidance.
In short, I'm wondering how to use TCP to communicate two Unity apps over the same computer. I've gotten it functioning in editor, but when both apps are built, communication quickly breaks down.
This is really stumping me, because I don't understand why an app would work in the Editor environment, but not in the official build.
When I use TCP to communicate between two Unity apps (on the same computer), it works so long as one of them is kept in the Unity environment. That is, if I build one app, and open the other in the Unity editor, TCP communication works flawlessly.
Here is some more background: One of my apps is functioning as a User Interface, and the other is interfacing with a Looking Glass to provide a holographic display of in-game objects. Originally, they were combined into one App - but I had a lot of trouble getting Unity's multidisplay support to function between two monitors of different resolutions. Looking Glass factory even provides a prefab to do just this, but it is broken in the current SDK. So I have resorted to using sockets to interface between two apps, one for each monitor.
I'm using C#'s TCP listener class: https://learn.microsoft.com/en-us/dotnet/api/system.net.sockets.tcplistener?view=netframework-4.8
And TCP client class: https://learn.microsoft.com/en-us/dotnet/api/system.net.sockets.tcpclient?view=netframework-4.8
Presently, the UI is acting as the TCPListener, and the application that produces holograms is the TCPClient. Within each of these applications, I'm using two Queues - an IncomingMessages queue and an Outgoing Messages queue - which are global variables shared between the main thread and the networking thread.
TCP Listener:
private void Start()
{
incomingMessages = new Queue();
outgoingMessages = new Queue();
Application.runInBackground = true;
thread = new Thread(new ThreadStart(Receive));
thread.Start();
//stuff happens that's irrelevant to this question. And then...
}
void Receive()
{
TcpListener server = null;
try
{
// Set the TcpListener on port 13000.
Int32 port = 13000;
IPAddress localAddr = IPAddress.Parse("127.0.0.1");
// TcpListener server = new TcpListener(port);
server = new TcpListener(localAddr, port);
// Start listening for client requests.
server.Start();
// Buffer for reading data
Byte[] bytes = new Byte[256];
String data = null;
// Enter the listening loop.
Debug.Log("About to reenter main while in Server...");
while (threadContinue)
{
Debug.Log("Waiting for a connection... ");
// Perform a blocking call to accept requests.
// You could also user server.AcceptSocket() here.
TcpClient client = server.AcceptTcpClient();
Debug.Log("Connected!");
data = null;
// Get a stream object for reading and writing
NetworkStream stream = client.GetStream();
int i;
// Loop to receive all the data sent by the client.
while ((i = stream.Read(bytes, 0, bytes.Length)) != 0)
{
// Translate data bytes to a ASCII string.
data = System.Text.Encoding.ASCII.GetString(bytes, 0, i);
Debug.Log("Received from Client: " + data);
lock (this)
incomingMessages.Enqueue(data);
string response = supplyData();
byte[] msg = System.Text.Encoding.ASCII.GetBytes(response);
// Send back a response.
stream.Write(msg, 0, msg.Length);
Debug.Log("Sent to Client: " + response);
}
// Shutdown and end connection
client.Close();
}
}
catch (SocketException e)
{
Debug.Log("SocketException: ");
Debug.Log(e);
}
finally
{
// Stop listening for new clients.
server.Stop();
}
Debug.Log("Exiting 'Receive'");
}
And here is the TCP Client. It attempts to connect a regular intervals, and also whenever new data is available. This is so that it can receive information from the server regularly and share new data whenever it is available:
void Start()
{
//prepare networking
Application.runInBackground = true;
outgoingMessages = new Queue();
incomingMessages = new Queue();
thread = new Thread(new ThreadStart(Connect));
thread.Start();
//stuff happens that's irrelevant to this question...
}
private void Connect()
{
String server = "127.0.0.1";
Int32 port = 13000;
string message = "";
while (threadContinue == true)
{
if (timeToConnect())
{
lastConnection = ourTime;
if (outgoingMessages.Count > 0)
message = outgoingMessages.Dequeue().ToString();
else
message = "Nothing to report.";
try
{
// Create a TcpClient.
// Note, for this client to work you need to have a TcpServer
// connected to the same address as specified by the server, port
// combination.
client = new TcpClient(server, port);
// Translate the passed message into ASCII and store it as a Byte array.
Byte[] data = System.Text.Encoding.ASCII.GetBytes(message);
// Get a client stream for reading and writing.
// Stream stream = client.GetStream();
stream = client.GetStream();
// Send the message to the connected TcpServer.
stream.Write(data, 0, data.Length);
Debug.Log("Sent to Server: " + message);
// Buffer to store the response bytes.
data = new Byte[256];
// String to store the response ASCII representation.
String responseData = String.Empty;
// Read the first batch of the TcpServer response bytes.
Int32 bytes = stream.Read(data, 0, data.Length);
responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes);
lock (this)
incomingMessages.Enqueue(responseData);
Debug.Log("Received from Server: " + responseData);
stream.Close();
client.Close();
}
catch (ArgumentNullException e)
{
Debug.Log("ArgumentNullException: ");
Debug.Log(e);
outgoingMessages.Enqueue(message);
}
catch (SocketException e)
{
Debug.Log("SocketException: ");
Debug.Log(e);
outgoingMessages.Enqueue(message);
}
}
}
}
private bool timeToConnect()
{
if ((ourTime - lastConnection > NETWORK_DELAY) || (outgoingMessages.Count > 0))
return true;
return false;
}
Instantiated in separate threads so that Unity's main thread can continue unhindered.
Again - it works in Editor, but when I build it, it breaks.
Update
I figured out what the problem was. I was trying to move too much data over TCP, and it was causing freeze-ups. For some reason, this wasn't manifesting in the editor...just in the exported app. Who knows for what reason. If anyone else stumbles upon this problem...where you're bypassing Unity's multidisplay functionality by building multiple apps that communicate over network...consider that you're burdening your queues with too much data.

How to stop my program from freezing up with TCP connection C#

I have created a TCP client and it connects fine but am a bit confused how to receive messages from the server without closing the connection ?
My current approach was to run a co-routine over the network stream read method but that freezes my program up so its obviously the wrong approach so am not sure how to fix it.
I want to keep the connection alive and read messages when ever they may arrive from the server.
This is what i have setup currently:
// the idea is to run a coroutine for recieving messages
private IEnumerator<float> _RunTCPSocket()
{
int timer = DateTime.Now.Second;
byte[] readBuffer = new byte[1024];
while (SocketManager.IsConnected)
{
// this is the keep alive packets to server to prevent timeout on server side
if (DateTime.Now.Second - timer > KeepAliveRate)
{
Debug.Log("Sending");
timer = DateTime.Now.Second;
SocketManager.Send(null);
}
int msgLength = SocketManager.Recieve(readBuffer);
if (msgLength > 0)
Debug.Log(Encoding.ASCII.GetString(readBuffer, 0, msgLength));
yield return Timing.WaitForOneFrame;
}
}
This is the code for the receive method:
public int Recieve(byte[] readBuffer)
{
if (!IsConnected)
return -1; //-1 signifies an error aka we are disconnected
try
{
// NetworkStream is from TcpClient.GetStream()
bytesRead = _networkStream.Read(readBuffer, 0, readBuffer.Length);
}
catch (Exception e)
{
IsConnected = false;
Debug.Log(e);
bytesRead = -1;
}
return bytesRead;
}
How do i prevent this from locking up my program ?
You can use Begin/End method to make your program responsible:
Document from microsoft
You can see that the using of BeginReceive method is so complex so personally, i don't think it's easy to use.
An alternative is to call the read/write method inside a Task.
The third option is use TcpClient which used on client side and TcpListener which used on server side. Those two class is just a wrapper for an underline TCP socket. Those wrapper can make your life much more easier with Stream and Async methods.
If you want to learn more about network programming with C#, i highly recomment this book: C# Network Programming by Richard Blum
Update
Code for working with Task:
public event EventHandler<ReceiveDataEventArgs> DataReceived = null;
public void StartReceive()
{
Task.Run(() =>
{
while (true)
{
var bytesRead = _networkStream.Read(readBuffer, 0, readBuffer.Length);
DataReceived?.Invoke(this, new ReceiveDataEventArgs
{
Data = bytesRead
});
}
});
}
public class ReceiveDataEventArgs : EventArgs
{
public byte[] Data { get; set; }
}

How to get IP addresses of hosts on local network running my program

I have built a peer to peer C# video conferencing application that uses a specific TCP port(17500) for audio communication. Currently, on my application interface, I enter the other IP address which has the program opened in order to communicate. What I want to do is to find the IP addresses automatically.
So, I though the best way to achieve this is to obtain the local IP addresses that are using the same TCP port number, 17500. How can I do that ? or is there any other methods getting IP addresses using the same application ?
As mentioned in comments, you need some kind of peer-discovery protocol.
As many multimedia devices, routers etc. use multicast based discovery protocols like SSDP, I created a similar discovery service sample .
Usage is simple. Just use
Discoverer.PeerJoined = ip => Console.WriteLine("JOINED:" + ip);
Discoverer.PeerLeft= ip => Console.WriteLine("LEFT:" + ip);
Discoverer.Start();
All your clients will use the same code.
using System;
using System.Net;
using System.Net.Sockets;
using System.Runtime.Caching; // add this library from the reference tab
using System.Text;
using System.Threading.Tasks;
namespace SO
{
public class Discoverer
{
static string MULTICAST_IP = "238.212.223.50"; //Random between 224.X.X.X - 239.X.X.X
static int MULTICAST_PORT = 2015; //Random
static UdpClient _UdpClient;
static MemoryCache _Peers = new MemoryCache("_PEERS_");
public static Action<string> PeerJoined = null;
public static Action<string> PeerLeft = null;
public static void Start()
{
_UdpClient = new UdpClient();
_UdpClient.Client.Bind(new IPEndPoint(IPAddress.Any, MULTICAST_PORT));
_UdpClient.JoinMulticastGroup(IPAddress.Parse(MULTICAST_IP));
Task.Run(() => Receiver());
Task.Run(() => Sender());
}
static void Sender()
{
var IamHere = Encoding.UTF8.GetBytes("I AM ALIVE");
IPEndPoint mcastEndPoint = new IPEndPoint(IPAddress.Parse(MULTICAST_IP), MULTICAST_PORT);
while (true)
{
_UdpClient.Send(IamHere, IamHere.Length, mcastEndPoint);
Task.Delay(1000).Wait();
}
}
static void Receiver()
{
var from = new IPEndPoint(0, 0);
while (true)
{
_UdpClient.Receive(ref from);
if (_Peers.Add(new CacheItem(from.Address.ToString(), from),
new CacheItemPolicy() {
SlidingExpiration = TimeSpan.FromSeconds(20),
RemovedCallback = (x) => { if (PeerLeft != null) PeerLeft(x.CacheItem.Key); }
}
)
)
{
if (PeerJoined != null) PeerJoined(from.Address.ToString());
}
Console.WriteLine(from.Address.ToString());
}
}
}
}
Now a little bit about the algorithm:
Every client multicasts a packet every seconds.
if the receiver(every client has it) gets a packet from an IP that isn't in its cache, it will fire PeerJoined method.
Cache will expire in 20 seconds. If a client doesn't receive a packet within that duration from another client in cache, it will fire PeerLeft method.
I believe if you are using a peer to peer application to exchange packets, when you need to know if someone "Is Online and Ready for connection", you need to send a broadcast. We can do it easily using an UDP connection.
I'll post an example where you use two methods: one to ask the entire network for ready clients in a broadcast message, and the other will start a listener to answer back broadcast asking message, or start a connection if a response of type "i am here" comes.
Hope it helps!
public sealed class UdpUtility
{
// Our UDP Port
private const int broadcastPort = 11000;
// Our message to ask if anyone is ready for connection
private const string askMessage = "ARE ANYONE OUT THERE?";
// Our answer message
private const string responseMessage = "I AM HERE!";
// We use this method to look for a client to connect with us.
// It will send a broadcast to the network, asking if any client is ready for connection.
public void SendBroadcastMessage()
{
var udp = new UdpClient(broadcastPort);
var endpoint = new IPEndPoint(IPAddress.Broadcast, broadcastPort);
try
{
var bytes = Encoding.ASCII.GetBytes(askMessage);
udp.Send(bytes, bytes.Length, endpoint);
}
catch (Exception ex)
{
// Treat your connection exceptions here!
}
}
// This method will start a listener on the port.
// The client will listen for the ask message and the ready message.
// It can then, answer back with a ready response, or start the TCP connection.
public void ListenBroadcastMessage()
{
var udp = new UdpClient(broadcastPort);
var endpoint = new IPEndPoint(IPAddress.Broadcast, broadcastPort);
bool received = false;
try
{
while (!received)
{
// We start listening broadcast messages on the broadcast IP Address interface.
// When a message comes, the endpoing IP Address will be updated with the sender IP Address.
// Then we can answer back the response telling that we are here, ready for connection.
var bytes = udp.Receive(ref endpoint);
var message = Encoding.ASCII.GetString(bytes);
if (message == askMessage)
{
// Our client received the ask message. We must answer back!
// When the client receives our response, his endpoint will be updated with our IP Address.
// The other client can, then, start the TCP connection and do the desired stuff.
var responseBytes = Encoding.ASCII.GetBytes(responseMessage);
udp.Send(responseBytes, responseBytes.Length, endpoint);
}
else if (message == responseMessage)
{
// We received a connection ready message! We can stop listening.
received = true;
// We received a response message!
// We can start our TCP connection here and do the desired stuff.
// Remember: The other client IP Address (the thing you want) will be on the
// endpoint object at this point. Just use it and start your TCP connection!
}
}
}
catch (Exception ex)
{
// Treat your connection exceptions here!
}
}
}
Invoke your command prompt to do "netstat -n" and extract the output.
Here is a piece of code taken from a program that I have wrote modified to fit your requirements. You will still need to further process the data to get the IP addresses
Process netP = new Process();
ProcessStartInfo netPI = new ProcessStartInfo();
netPI.FileName = "cmd";
netPI.UseShellExecute = false;
netPI.RedirectStandardOutput = true;
netPI.RedirectStandardInput = true;
netPI.RedirectStandardError = true;
netPI.CreateNoWindow = true;
netP.StartInfo = NetPI;
netP.Start();
while (!netP.Start())
Thread.Sleep(100);
StreamWriter sW = netP.StandardInput;
StreamReader sR = netP.StandardOutput;
sW.WriteLine("netstat -n")
sW.Close();
string data = sR.ReadToEnd();
sR.Close();
//Do some further processing to filter out the addresses and extract

Detect SQL event with C# application

I have the code below (a literal copy/paste from MSDN website just to be clear), which seems to connect as it should (except for an "Access Denied" error which is okay because my security requests haven't gone through yet). What I need to do is detect when our sql server has executed an insert or update operation. Basically this application should be running 24/7 and perform certain functions when an operation as such comes across the listener. I'm not asking for the code to be laid out in front of me, but I am asking where to start. This is something I have no clue how to do at this point and am being told I have roughly a week to figure it out and get it done. Can someone point me in the right direction? Thank you in advance!
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
namespace Connect_Server
{
class Program
{
static string output = "";
static void Main(string[] args)
{
createListener();
}
static public void createListener()
{
// Create an instance of the TcpListener class.
TcpListener tcpListener = null;
IPAddress ipAddress = Dns.GetHostEntry("localhost").AddressList[0];
try
{
// Set the listener on the local IP address
// and specify the port.
tcpListener = new TcpListener(ipAddress, 80);
tcpListener.Start();
output = "Waiting for a connection...";
}
catch (Exception e)
{
output = "Error: " + e.ToString();
Console.Write(output);
}
while (true)
{
// Always use a Sleep call in a while(true) loop
// to avoid locking up your CPU.
Thread.Sleep(10);
// Create a TCP socket.
// If you ran this server on the desktop, you could use
// Socket socket = tcpListener.AcceptSocket()
// for greater flexibility.
TcpClient tcpClient = tcpListener.AcceptTcpClient();
// Read the data stream from the client.
byte[] bytes = new byte[256];
NetworkStream stream = tcpClient.GetStream();
stream.Read(bytes, 0, bytes.Length);
SocketHelper helper = new SocketHelper();
helper.processMsg(tcpClient, stream, bytes);
}
}
}
}
Check out SQL Server Notifications. This will send a signal to your app when some underlying dataset changes. I'm not sure how heavy this is for the server, so if you have a large number of clients waiting for a notification you should load-test it carefully....

Cannot figure out how to get Socket to receive data C#

So what I am specifically trying to do is get a serial proxy going to pipe an arduino into Unity3d to run on linux. System.IO.Ports just doesn't work on linux with unity.
So I have gotten a python based serial proxy script, I have that up and running just fine. I can netcat into that localhost and actually get output from the arduino.
nc localhost 8082
g'day from bitty 1.0 -- type 'logout' to disconnect
Connecting to /dev/tty.usbmodem5d11... connected.
HELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLOHELLO
I have the arduino only printing out HELLO on repeat.
But the serial proxy is up and running, and has data going over it.
Now I am trying to write the code in Unity to receive this data, and I just can't get it to work.
This is my code for that:
public Socket socket = new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
public byte[] buffer = new byte[256];
int pinRead = 0;
void Start ()
{
socket.Connect(IPAddress.Parse("127.0.0.1"),8082);
}
void Update ()
{
if (socket.IsBound)
{
try
{
int bytesRead;
bytesRead = socket.Receive(buffer);
string incommingdata = System.Text.Encoding.ASCII.GetString(buffer);
Debug.Log(bytesRead+" || "+incommingdata);
}
catch (System.Exception e)
{
}
}
bytesRead is ALWAYS 0 and incomingData just doesn't have anything. It connects, and isBound returns true. I just can't get the code right to receive the data and put it in a format that is usable.
Please help. I need to get this working and its far out of my area of expertise. How do I make this work?
So I got this to work using tcpclient objects and some snippets of code that were posted on a random unity blog....
Here it is if anyone wants to see. I would still be really curious to know how to get the Socket implementation functioning though.
using UnityEngine;
using System.Collections;
using System.Net;
using System.Net.Sockets;
using System;
using System.Text;
using System.IO;
using System.Threading;
public class ArduinoTest : MonoBehaviour
{
private bool socketReady = false;
private TcpClient mySocket;
private NetworkStream theStream;
private StreamWriter theWriter;
private StreamReader theReader;
private string Host = "localhost";
private Int32 Port = 9900;
private int pinRead = 0;
void Start ()
{
setupSocket();
}
void Update ()
{
string read = readSocket();
if (read != "")
{
int value = int.Parse(read);
if ( value > 53)
{
Debug.Log((value-54)+" DOWN");
}
else
{
Debug.Log(value+" UP");
}
}
}
void OnApplicationQuit()
{
writeSocket("logout");
closeSocket();
}
public void setupSocket()
{
try
{
mySocket = new TcpClient(Host, Port);
theStream = mySocket.GetStream();
theWriter = new StreamWriter(theStream);
theReader = new StreamReader(theStream);
socketReady = true;
}
catch (Exception e)
{
Debug.Log("Socket error:" + e);
}
}
public void writeSocket(string theLine)
{
if (!socketReady)
return;
String tmpString = theLine + "\r\n";
theWriter.Write(tmpString);
theWriter.Flush();
}
public string readSocket()
{
if (!socketReady)
return "";
if (theStream.DataAvailable)
return theReader.Read().ToString();
return "";
}
public void closeSocket()
{
if (!socketReady)
return;
theWriter.Close();
theReader.Close();
mySocket.Close();
socketReady = false;
}
public void maintainConnection()
{
if(!theStream.CanRead)
{
setupSocket();
}
}
}
(Sorry I can't post comments yet or would do so there)
BytesRead = 0 typically means the remote side disconnected.
For what it's worth, your code works fine when I run a test TCP server listening for connections on port 8082 and sending out some text messages. So I doubt the problem is on the C# client-side.
Beyond this simple example, "getting this to work" is not necessarily a simple question. Here are a couple things you should keep in mind:
You are making a blocking Receive call, which means you will need to call Update in a loop.
TCP is a streaming protocol, so you might get partial messages or many messages bundled together in the same Read call. Look up "TCP Framing" to get more details on this.
You can try using telnet on this socket, just to see if you can connect to it.
telnet 127.0.0.1 8082

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