Could somebody take a look at my socket code

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C#

C#4.0

sockets

Dear reader,

I am wondering if i am going about this socket programming all wrong. My code is functional but i just have my doubts this is correct. I will be posting code in execution order.

Server:

Listen for connections

mainSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

IPEndPoint ipLocal = new IPEndPoint(IPAddress.Any, 1500);
mainSocket.Bind(ipLocal);
mainSocket.Listen(-1);

mainSocket.BeginAccept(new AsyncCallback(OnClientConnect), null);

//Request a file
//Set first to transfer command, 1-8 uri length, ASCII data

private void TransferFile(string uri)
{
    byte[] tmp = ASCIIEncoding.ASCII.GetBytes(uri);
    byte[] data = new byte[tmp.Length + 9];
    BitConverter.GetBytes((long)tmp.Length).CopyTo(data, 1);
    tmp.CopyTo(data, 9);
    data[0] = (byte)cmd.transfer;
    SendPacket(clientSocket, data);
}
public void SendPacket(SocketPacket to, byte[] p)
{
    if (!IsConnected(to.currentSocket))
    {
        Disconnect(to);
        return;
    }
    try
    {
        NetworkStream networkStream = new NetworkStream(to.currentSocket);
        networkStream.Write(p, 0, p.Length);
    }
    catch (Exception)
    {
    }
}

Client:

//connect to server and wait for commands

public void start()
{
try
{
    clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
    clientSocket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, 1);
    IPEndPoint ipEnd = new IPEndPoint(IPAddress.Loopback, 1500);
    clientSocket.Connect(ipEnd);
    WaitForData();
}
catch (Exception)
{
}
}

public void WaitForData()
{
try
{
    if (pfnCallBack == null)
    {
        pfnCallBack = new AsyncCallback(OnDataReceived);
    }
    SocketPacket theSocPkt = new SocketPacket(clientSocket);
    result = clientSocket.BeginReceive(theSocPkt.Buffer, 0, 9, SocketFlags.None, pfnCallBack, theSocPkt);
}
catch (Exception)
{}
}

//File transfer request received

public void OnDataReceived(IAsyncResult asyn)
{
try
{
    byte[] tmp = new byte[1024];
    string msg = string.Empty;
    long length = 0;
    long rdby = 0;
    int len = 0;
    SocketPacket s = (SocketPacket)asyn.AsyncState;
    NetworkStream nfs = new NetworkStream(s.currentSocket);

    //Read byte 1-8 from BeginReceive buffer to length
    length = BitConverter.ToInt64(s.Buffer, 1);
    //Read byte 0 with command
    switch (s.Buffer[0])
    {
        case (int)cmd.transfer:
        while (rdby < length)
        {
            len = nfs.Read(tmp, 0, pSize);
            if (len == 0) if (!IsConnected(s.currentSocket)) { Dispose(); Start(); };
            msg += ASCIIEncoding.ASCII.GetString(tmp, 0, len);
            rdby = rdby + len;
        }
        SendFile(s.currentSocket, msg);
        break;
   }
}
catch (Exception)
{}
WaitForData();
}

public void SendFile(Socket s, string file)
{
try
{
    if (clientSocket != null)
    {
        FileInfo fi = new FileInfo(file);

        int len = 0;
        int rdby = 0;

        FileStream fin = new FileStream(file, FileMode.Open, FileAccess.Read);
        NetworkStream nfs = new NetworkStream(s);

        //Send Header, 0= cmd, 1-8 file length
        byte[] tmp = new byte[9];
        BitConverter.GetBytes(fi.Length).CopyTo(tmp, 1);
        tmp[0] = (byte)cmd.transfer;
        nfs.Write(tmp, 0, tmp.Length);

        //Send File
        tmp = new byte[pSize];
        while (rdby < fi.Length && nfs.CanWrite)
        {
            len = fin.Read(tmp, 0, tmp.Length);
            nfs.Write(tmp, 0, len);
            rdby = rdby + len;
        }
        fin.Close();
    }
}
catch { }
}

private bool IsConnected(Socket socket)
{
    try
    {
        if (socket.Connected)
            return !(socket.Poll(100, SelectMode.SelectRead) && socket.Available == 0);
        else
            return false;
    }
    catch (SocketException) { return false; }
}

Thanks for baring with me,
And hopefully i can learn something from your response.