I am working on TCP multithread server with C# window application form, and I am trying to detect if the machine of client is shutdown and disconnects from the server. I have read some posts and have some ideas:
How to determine if the tcp is connected or not?
Instantly detect client disconnection from server socket
But I'm not sure where to call the function IsConnected
My code is like the following:
public BindingList<Tablet> tabletList = new BindingList<Tablet>();
private Socket socket_Server = null;
private Thread myThread = null;
private Socket socket_Connect = null;
private Dictionary<string, Socket> dic = new Dictionary<string, Socket> { };
private string RemoteEndPoint;
socket_Server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPAddress ServerIP = IPAddress.Parse("192.168.2.146");
IPEndPoint point = new IPEndPoint(ServerIP, portNum);
socket_Server.Bind(point);
socket_Server.Listen(50);
myThread = new Thread(Listen_Disp);
myThread.IsBackground = true;
myThread.Start();
Console.WriteLine("Server start");
private void Listen_Disp()
{
try
{
while (true)
{
//This is not working
for (int i = 0; i < tabletList.Count; i++)
{
if (!SocketConnected(dic[tabletList[i].ip]))
{
Console.WriteLine(RemoteEndPoint + "disconnected");
}
}
try
{
socket_Connect = socket_Server.Accept();
RemoteEndPoint = socket_Connect.RemoteEndPoint.ToString();
Console.WriteLine(RemoteEndPoint + " is connected");
dic.Add(RemoteEndPoint, socket_Connect);
Tablet newTablet = new Tablet();
newTablet.ip = RemoteEndPoint;
newTablet.status = "Online";
tabletList.Add(newTablet);
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
Console.WriteLine("end of while");
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
static class SocketExtensions
{
public static bool IsConnected(this Socket socket)
{
try
{
return !(socket.Poll(1, SelectMode.SelectRead) && socket.Available == 0);
}
catch (SocketException) { return false; }
}
}
Thanks for help.