C#socket Communication Server (Connection status monitoring)

Class Socketservermanager
{
public delegate void Connectstateeventhandler ();
Public event Connectstateeventhandler connectedevent;//Client Connection
Public event Connectstateeventhandler disconnectedevent;//client off-line

public delegate void Receivemsgeventhandler (byte[] order);
public event Receivemsgeventhandler Receivemsgevent;

static Socket _socket = null;
static IPEndPoint IEP = NULL;
static bool islistening = FALSE;
static bool isconnected = FALSE;
Static Dictionary<endpoint, socket> dic = null;
static EndPoint EP = null;

Public Socketservermanager (string Strip,int port)
{
_socket = new Socket (addressfamily.internetwork, SocketType.Stream, protocoltype.tcp);
IPAddress IP = Ipaddress.parse (Strip.trim ());
IEP = new IPEndPoint (IP, Port);
Dic=new dictionary<endpoint,socket> ();
}

public void Start ()
{
_socket. Bind (IEP);
Islistening = true;
Thread t = new thread (Listen);
T.isbackground = true;
T.start ();
}

private void Listen ()
{
while (islistening)
{
_socket. Listen (0);
Socket Newsocket = _socket. Accept ();
if (connectedevent! = null) connectedevent ();
EP = Newsocket. Remoteendpoint;
Dic. ADD (EP, Newsocket);
IsConnected = true;
thread T1 = new Thread (RECEIVEMSG);
T1. IsBackground = true;
T1. Start ();
}
}

private void Receivemsg ()
{
while (isconnected)
{
Byte[] Buffer=new byte[32];
int count = Dic[ep]. Receive (buffer);
if (Count > 0&&receivemsgevent! = null)
{
Receivemsgevent (buffer);
}
if (! Issocketconnected (Dic[ep]) && disconnectedevent! = null)
{
Disconnectedevent ();
IsConnected = false;
}
Thread.Sleep (200);
}
}

public void sendmsg (byte[] order)
{
DIC[EP]. Send (Order,order. Length,socketflags.none);
}

private bool Issocketconnected (Socket s)
{
Return! ((S.poll (Selectmode.selectread) && (s.available = = 0)) | |!s.connected);
}
}

C#socket Communication Server (Connection status monitoring)