I'm writing a C# console application using the 32feet.Net library that creates two threads to search for and connect to different Bluetooth devices and then open up TCP sockets so that data can be passed to the devices via a network connection. I know this situation sounds completely bizarre, but I've been asked to do this by a senior colleague.
My code seems to work OK with only one device connected, although the Bluetooth connection does sometimes drop out after a couple of messages have been passed backwards and forwards. However, sometimes as soon as the second device connects I get an error saying System.net.sockets.socketexception a connection attempt failed because the connected party did not properly respond, other times the code just exits without throwing any exceptions.
I was wondering what is causing this, I've seen that the 32feet.Net library can support multiple connections. I'm wondering if I've made some errors, as I'm new to C#, .Net, and even Windows, and have never written any Bluetooth based code before.
Program.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
namespace BluetoothManager
{
class Program
{
static void Main(string[] args)
{
BTManager rover_btm = new BTManager();
BTManager base_btm = new BTManager();
base_btm.Port = 0xba5e;
rover_btm.Port = 17825;
base_btm.Name = "Base";
rover_btm.Name = "Rover";
base_btm.match = (args.Length >= 1 && args[0] != "") ? args[0] : "dev1";
rover_btm.match = (args.Length >= 2 && args[1] != "") ? args[1] : "dev2";
Console.WriteLine("Base Station match: " + base_btm.match);
Console.WriteLine("Rover match: " + rover_btm.match);
Thread Base = new Thread(new ThreadStart(base_btm.HandleThread));
Thread Rover = new Thread(new ThreadStart(rover_btm.HandleThread));
Base.Start();
Rover.Start();
Base.Join();
Rover.Join();
Console.Read();
}
}
}
BTManager.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using InTheHand.Net.Bluetooth;
using InTheHand.Net.Ports;
using InTheHand.Net.Sockets;
using System.Threading;
using System.Net;
using System.Net.Sockets;
using Microsoft.Win32;
using System.IO;
namespace BluetoothManager
{
class BTManager
{
private static BluetoothDeviceInfo[] peers;
private BluetoothClient client;
private bool _isConnected = false;
private string _match;
private const string defpin = "0000";
private TcpListener tcpListener;
private int _port;
private string _name = "Not Named";
public string Name
{
get { return _name; }
set { _name = value; }
}
public int Port
{
get { return _port; }
set { _port = value; }
}
public bool IsConnected
{
get { return _isConnected; }
private set { _isConnected = value; }
}
public string match
{
get { return _match; }
set { _match = value; }
}
public BTManager()
{
client = new BluetoothClient();
}
public void HandleThread()
{
BluetoothDeviceInfo device;
while (!this.findDevice(out device)) ;
Console.WriteLine("About to pair");
int count = 0;
int max = 5;
while ((!(BluetoothSecurity.PairRequest(device.DeviceAddress, defpin))) && count < max)
{
Console.WriteLine("Pairing Failed, retrying");
count++;
Thread.Sleep(100);
}
if (count == max)
{
HandleThread();
}
else
{
Console.WriteLine("Paired..Beginning connect");
client.BeginConnect(device.DeviceAddress, BluetoothService.SerialPort, this.callback, client);
}
}
private void callback(IAsyncResult result)
{
client.EndConnect(result);
this.tcpListener = new TcpListener(IPAddress.Loopback, _port);
this.tcpListener.Start();
TcpClient TcpClient = this.tcpListener.AcceptTcpClient();
NetworkStream networkStream = TcpClient.GetStream();
Stream bluetoothStream = client.GetStream();
byte[] fromNetwork = new byte[1024];
byte[] fromBluetooth = new byte[1024];
while (client.Connected && TcpClient.Connected)
{
try
{
if (networkStream.CanRead)
{
Array.Clear(fromNetwork, 0, 1024);
networkStream.Read(fromNetwork, 0, 1024);
Console.WriteLine(Encoding.ASCII.GetString(fromNetwork));
bluetoothStream.Write(fromNetwork, 0, 1024);
bluetoothStream.Flush();
while (bluetoothStream.CanRead)
{
Array.Clear(fromBluetooth, 0, 1024);
bluetoothStream.Read(fromBluetooth, 0, 1024);
Console.WriteLine(Encoding.ASCII.GetString(fromNetwork));
networkStream.Write(fromBluetooth, 0, 1024);
networkStream.Flush();
}
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
this.HandleThread();
}
private bool findDevice(out BluetoothDeviceInfo device)
{
peers = client.DiscoverDevicesInRange();
device = Array.Find(peers, element => element.DeviceName == match);
foreach (BluetoothDeviceInfo btdi in peers)
{
Console.WriteLine(btdi.DeviceName);
}
if (device == null)
{
Console.WriteLine(Name +": Not Found");
return false;
}
else
{
Console.WriteLine(Name +": Found");
return true;
}
}
}
}
