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C# tcpclient not writing to socket...or maybe I'm not reading all of the response?

I'm trying to write a C# console app to interface with a PC Miler telnet server. I managed to get this to work in powershell, but my C# code is not working.
static void Main(string[] args)
{
byte[] ReadBuffer = new byte[1024];
string[] stringSeparators = new string[]{"READY"};
try
{
TcpClient Socket = new TcpClient("myServer", 8320);
if (Socket.Connected) {
NetworkStream netStream = Socket.GetStream();
string PCMSResponse = "";
// Check for the READY prompt
if (netStream.CanRead) {
int byteRead = 0;
while (netStream.DataAvailable) {
byteRead = netStream.Read(ReadBuffer, 0, ReadBuffer.Length);
PCMSResponse += Encoding.ASCII.GetString(ReadBuffer, 0 , byteRead).Trim();
}
} else {
Console.WriteLine("Cannot read from myServer");
}
Thread.Sleep(1000);
// Get New Trip
if (netStream.CanWrite) {
Byte[] PCMSCommandBuffer = Encoding.ASCII.GetBytes("PCMSNewTrip");
netStream.Write(PCMSCommandBuffer, 0 , PCMSCommandBuffer.Length);
Thread.Sleep(1000);
} else {
Console.WriteLine("Cannot write to myServer.");
}
if (netStream.CanRead) {
int byteRead = 0;
while (netStream.DataAvailable) {
byteRead = netStream.Read(ReadBuffer, 0, ReadBuffer.Length);
PCMSResponse += Encoding.ASCII.GetString(ReadBuffer, 0, byteRead).Trim();
}
} else {
Console.WriteLine("Cannot read from myServer");
}
string[] ResponseArray = PCMSResponse.Split(stringSeparators, StringSplitOptions.None);
int c = ResponseArray.Length - 2;
string TripID = ResponseArray[c].Replace(System.Environment.NewLine, "").Replace("\0", "");
Console.WriteLine(PCMSResponse);
}
}
catch (SocketException)
{
Console.WriteLine("Unable to connect to server")
}
}
Expected output
ALK PCMILER SERVER READY
pcmsnewtrip
53
READY
Actual output
ALK PCMILER SERVER READY
It seems like I am not actually writing to the server because if I were to write an invalid command to the server I would see an error like this:
ALK PCMILER SERVER READY
pmctripnew
NO SUCH FUNCTION
READY
I know I can write to the socket because I'm not getting my error message Cannot write to myServer.
Not sure what I'm doing wrong. :(
Let me know if you'd also like to see the powershell code.
EDIT - If you're going to edit this post, at least keep the expected output AS EXPECTED! Changing the expected output changes the intent of the post. (EG, if I want apples but you edit my post to ask for oranges, I'm not going to get the correct answer.)

So the issue turns out to be that the NetworkStream.Write method does not end a string with a line terminator. As a result, when I wrote my PCMSCommandBuffer bytes to the stream, the command was never processed by the server (because its waiting for more of the command or the enter key to let it know you're done). My solution was to assign the stream to a StreamWriter. Then I can use the WriteLine method whichdoes send a line terminator.
streamWriter = new StreamWriter(netStream);
// Get New Trip
if (netStream.CanWrite) {
Byte[] PCMSCommandBuffer = Encoding.ASCII.GetBytes("PCMSNewTrip");
//netStream.Write(PCMSCommandBuffer, 0 , PCMSCommandBuffer.Length);
streamWriter.WriteLine("PCMSNewTrip");
//netStream.Flush();
streamWriter.Flush();
Console.WriteLine(PCMSCommandBuffer.Length + " PCMSNewTrip");
Thread.Sleep(1000);
} else {
Console.WriteLine("Cannot write to EW-APP1.");
}

C#/Unity - Convert StreamWriter.WriteLine to StreamWriter.Write and Message Bytes size as prefix

I've been researching and came to the conclusion that using StreamWriter.WriteLine is not the best idea. However, using StreamWriter.Write and prefixing the actual message bytes size and sending it from the client to the server so the server will know where to start reading and where to stop reading.
Here is working code I have so far:
public void Send(string header, Dictionary<string, string> data)
{
new Thread(() =>
{
Thread.CurrentThread.IsBackground = true;
if (stream.CanRead)
{
socketReady = true;
}
if (!socketReady)
{
return;
}
JsonData SendData = new JsonData();
SendData.header = "1x" + header;
foreach (var item in data)
{
SendData.data.Add(item.Key.ToString(), item.Value.ToString());
}
SendData.connectionId = connectionId;
string json = JsonConvert.SerializeObject(SendData);
byte[] JsonToBytes = Encoding.ASCII.GetBytes(json);
byte[] lengthArray = BitConverter.ToInt32(JsonToBytes, 0);
stream.Write(lengthArray, 0, lengthArray.Length);
stream.Write(JsonToBytes, 0, JsonToBytes.Length);
stream.Flush();
Debug.Log("Client World:" + json);
}).Start();
}
This is how I send the data to the server. As you see I'm using writer.WriteLine(json); I know that I need to change that first to calculate the size of the message in bytes and send it as a prefix.
Here is how i read the data at the server:
//Console.WriteLine("Call");
if (!serverStarted)
{
return;
}
foreach (ServerClient c in clients.ToList())
{
// Is the client still connected?
if (!IsConnected(c.tcp))
{
c.tcp.Close();
disconnectList.Add(c);
Console.WriteLine(c.connectionId + " has disconnected.");
CharacterLogout(c.connectionId);
continue;
//Console.WriteLine("Check for connection?\n");
}
else
{
// Check for message from Client.
NetworkStream s = c.tcp.GetStream();
if (s.DataAvailable)
{
string data = c.streamReader.ReadLine();
if (data != null)
{
OnIncomingData(c, data);
}
}
//continue;
}
}
for (int i = 0; i < disconnectList.Count - 1; i++)
{
clients.Remove(disconnectList[i]);
disconnectList.RemoveAt(i);
}
As you see I'm using c.streamReader.ReadLine(); which is reading the Line as a delimiter. I don't want that. I need to change it to check the message size in bytes, read it and then send it to OnIncomingData(c, data); as an actual message without the bytes prefix.
However, I don't know how to calculate the actual message size in the client, form it and send it. I'm also not aware how to proceed it in the reading in the server.
Can you please review my code and make edits to my code so it will work in this manner and I can understand how it works?

TCP IP Client in WPF for Ubuntu 14 Server

I am trying to create TCP IP Client in WPF GUI / C#.NET for a Ubunu Server.
Problem: I am able to connect to the server machine , the connection work correctly, send the message correctly and the ubuntu console show as well , Client Connected and sent this command like Start Video Feed on the server but When it comes to Read the Response nothing happens - It does not read the byte array that should be returned by the Ubuntu Server. Actually on message - 102 it should start the video feed on the server and return back the video feed byte array which should be read further and display the video. No code written yet to display the video feed as I am unable to read the feed from the server however, the client sends the commands(messages) to the server correctly as mentioned can view it on a console of the Ubuntu server machine. Please suggest thanks !!
Below is the code please have a look and suggest me what I am doing wrong :
namespace POC_TCP_Listener
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private int WhichEventFired = 0;
private void Button_Click_1(object sender, RoutedEventArgs e)
{
try
{
// string message = "{Site: 1}";
WhichEventFired = 1; //Start Video Feed
Thread ClientThread = new Thread(new ThreadStart(ConnectToServerAndRetrieveBytes));
ClientThread.Start();
}
catch (Exception ex)
{
string st = ex.Message;
}
}
private void ConnectToServerAndRetrieveBytes()
{
TcpClient TCP = new TcpClient();
TCP.Connect("IPAddress", 5001);
byte[] packet;
var size = 9;
var header = 102;
var siteId = 1;
var state = 1;
if (WhichEventFired == 1)
{
header = 102; // Start Video Feed
}
else if (WhichEventFired == 2)
{
header = 114; // Stop Video Feed
}
else
{
header = 115; // query Temperature
}
// <8> <115> <1>
packet = BitConverter.GetBytes(size).Reverse().Concat(BitConverter.GetBytes(header).Reverse()).Concat(BitConverter.GetBytes(siteId).Reverse()).Concat(BitConverter.GetBytes(state).Reverse()).ToArray();
// Translate the passed message into ASCII and store it as a Byte array.
Byte[] data = packet;
// Get a client stream for reading and writing.
NetworkStream stream = TCP.GetStream();
// Send the message to the connected TcpServer.
stream.Write(data, 0, data.Length);
byte[] buffer = new byte[64 * 1024];
using (MemoryStream ms = new MemoryStream())
{
int read;
// In the below line - it stops and nothing happens after it - Please Suggest
while ((read = stream.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
}
// return ms.ToArray();
}
stream.Close();
TCP.Close();
}
}
}
strong text
Please suggest why it stops working or let me know if I am doing anything wrong.

I think the problem is that if there are no more packages left, it escapes the while-loop. If you want to check it endlessly you should try using a for. But i am not sure.
Yeah that should be it. If there are no Packages in the moment the while-loop is starting, it terminates itself because there is nothing to read. So you could check if the Ubuntu Server returns you something.

C# sockets: can't read after writing to socket

In my client/server application my client wiil communicate with the server for 2 functions: the client will either request data from the server or it will send data so the server will save it. I'm using one socket for both methods, and the method to be used is defined by the first byte sent. If the first byte is "1" it is requesting data. If it is "2", it will send data (data bytes are sent after the "2" byte). It works perfectly for sending data. But when I'm requesting data it works, as long as I don't read the socket stream in the client. It's like if I make the client read data after sending data, the server will have no data to read, and it just crashes when trying to read the data.
Here is my server code:
private const int BufferSize = 1024;
NetworkStream netstream = null;
byte[] RecData = new byte[BufferSize];
int RecBytes;
try {
netstream = clientSocket.GetStream();
int totalrecbytes = 0;
using (MemoryStream ms = new MemoryStream()) {
//When I get here, there is no data to read
while ((RecBytes = netstream.Read(RecData, 0, RecData.Length)) > 0) {
ms.Write(RecData, 0, RecBytes);
totalrecbytes += RecBytes;
}
byte[] bytes = ms.ToArray();
byte b = bytes[0];
switch (b) {
case 1:
//Here I gather data and put it in "stream" variable
byte[] SendingBuffer = null;
int NoOfPackets = Convert.ToInt32(Math.Ceiling(Convert.ToDouble(stream.Length) / Convert.ToDouble(BufferSize)));
int TotalLength = (int)stream.Length, CurrentPacketLength, counter = 0;
for (int i = 0; i < NoOfPackets; i++) {
if (TotalLength > BufferSize) {
CurrentPacketLength = BufferSize;
TotalLength = TotalLength - CurrentPacketLength;
}
else
CurrentPacketLength = TotalLength;
SendingBuffer = new byte[CurrentPacketLength];
stream.Read(SendingBuffer, 0, CurrentPacketLength);
netstream.Write(SendingBuffer, 0, (int)SendingBuffer.Length);
}
netstream.Flush();
}
catch (Exception e) {
Console.WriteLine("EXCEPTION:\n" + e.ToString());
}
break;
case 2:
//Code to read data
break;
}
}
netstream.Close()
clientSocket.Close();
And here is my client code:
using (System.Net.Sockets.TcpClient clientSocket = new System.Net.Sockets.TcpClient()) {
string returnData = "";
IAsyncResult ar = clientSocket.BeginConnect("127.0.0.1", 8080, null, null);
System.Threading.WaitHandle wh = ar.AsyncWaitHandle;
try {
if (!ar.AsyncWaitHandle.WaitOne(TimeSpan.FromSeconds(5), false)) {
clientSocket.Close();
Console.WriteLine("Timeout");
return;
}
System.Net.Sockets.NetworkStream serverStream = clientSocket.GetStream();
byte b = 1;
byte[] outStream = { b };
serverStream.Write(outStream, 0, outStream.Length);
serverStream.Flush();
//If I comment following lines, the server can read sent data, but server can't otherwise
byte[] RecData = new byte[1024];
int RecBytes;
int totalrecbytes = 0;
MemoryStream MS = new MemoryStream();
while ((RecBytes = serverStream.Read(RecData, 0, RecData.Length)) > 0) {
MS.Write(RecData, 0, RecBytes);
totalrecbytes += RecBytes;
}
serverStream.Close();
clientSocket.Close();
clientSocket.EndConnect(ar);
}
catch (Exception ex) {
Console.WriteLine("Exceção: " + ex.ToString());
}
finally {
wh.Close();
}
}
So, how can I send data to server and read the response? (I tried even putting the thread to sleep after sending data, with no luck.)
Thanks in advance.
EDIT:
With some debug messages I discovered that the server do read the "1" byte that was sent, but somehow it gets stuck inside the while loop, like, the server just stops there, no more loops and it does not leave the while loop. I saw that after writing "loop" in console inside the while loop, and writing read bytes also in console. It wrote "loop" once, and the read byte.

This code worries me:
//When I get here, there is no data to read
while ((RecBytes = netstream.Read(RecData, 0, RecData.Length)) > 0) {
ms.Write(RecData, 0, RecBytes);
totalrecbytes += RecBytes;
}
You are reading until the client closes the connection (or shuts down sending, which you don't do). But the client only closes when the server has replied. The server reply will never come. It is a deadlock.
Solution: Read a single byte to determine the requests command (b).
Unrelated to the question, your "packetised" sending (NoOfPackets, ...) does not seem to serve any purpose. Just use Stream.Copy to write. TCP does not have packets.
An even better solution would be to abandon your custom TCP protocol and use an HTTP library. All these concerns just go away. There are various smaller problems with your code that are very typical to see in TCP code.

TcpListener truncating byte array randomly

I am writing what is essentially an image backup server to store images. It is a one way service that will not return anything beyond a basic success or failure message to the client.
The issue that I am experienceing is that when I send a byte array through the network stream, it is being cut-off before the end of the stream at random locations. I do not have this issue when I run the server on my development machine and connect locally, but rather it only occurs when the server is deployed on a remote server.
When I send very small arrays ( < 512 bytes) the server recieves the entire stream successfully, but on streams larger than 2000 bytes I experience issues. The code for the client is as follows:
try
{
TcpClient Voice = new System.Net.Sockets.TcpClient();
//Obviously I use the remote IP when it is deployed - but have altered it for privacy.
IPEndPoint BackupServer = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 57000);
Voice.Connect(BackupServer);
NetworkStream DataStream = Voice.GetStream();
byte[] buffer = new ASCIIEncoding().GetBytes(ImageData.GetXml());
DataStream.Write(buffer, 0, buffer.Length);
DataStream.Flush();
}
catch
{
}
try
{
buffer = new byte[4096];
int read = DataStream.Read(buffer, 0, buffer.Length);
MessageBox.Show(new ASCIIEncoding().GetString(buffer) + " : " + read.ToString());
}
catch
{
}
The client code executes without any errors or problems regardless of the size of data I send.
And the code for the server side is as follows:
private void BackMeUp(object voice)
{
TcpClient Voice = (TcpClient)voice;
Voice.ReceiveTimeout = 30000;
NetworkStream DataStream = Voice.GetStream();
try
{
bool ShouldLoop = true;
//int loops = 0;
int loops = -1;
byte[] input = new byte[2048];
byte[] buffer = new byte[0];
//while (ShouldLoop)
while(loops != 0)
{
loops = DataStream.Read(input, 0, 2048);
for (int x = 0; x < loops; x++)
{
Array.Resize(ref buffer, buffer.Length + 1);
buffer[buffer.Length - 1] = input[x];
}
//if (loops < 2048)
//{
//ShouldLoop = false;
//break;
//}
}
while (true)
{
StringReader Reader = new StringReader(new ASCIIEncoding().GetString(buffer, 0, buffer.Length));
DataSet DS = new DataSet();
DS.ReadXml(Reader);
if (DS.Tables.Count > 0)
{
if (DS.Tables["Images"].Rows.Count > 0)
{
foreach (DataRow row in DS.Tables["Images"].Rows)
{
//
}
}
}
string response = "Got it!";
DataStream.Write(new ASCIIEncoding().GetBytes(response), 0, response.Length);
DataStream.Flush();
Voice.Close();
break;
}
}
catch (Exception Ex)
{
File.WriteAllText("Elog.txt", Ex.Message + " " + (Ex.InnerException != null ? Ex.InnerException.ToString() : " no Inner"));
Voice.Close();
}
}
The server recieves the data fine, and closes the stream when it reaches the end, however the data is cut-off and I get an error when I try to rebuild the dataset.
I have the impression this has to do with the time it takes to send the stream, and I have played around with the Close and Flush commands but I feel like I'm just shooting in the dark. Any help would be appreciated.
Concise version of question: What factors are involved with a TcpListener that could cause a) the truncation of the stream. or b) premature closing of the stream prior to all bytes being read. When the listener in question is on a remote host rather than a local server.

The Read method doesn't have to return the number of bytes that you requested, or the entire stream at once. Especially if the stream is slow, it will be returned in small chunks.
Call the Read method repeatedly, and handle the data for each block that you get. The Read method returns zero when the stream is read to the end:
buffer = new byte[4096];
do {
int read = DataStream.Read(buffer, 0, buffer.Length);
if (read != 0) {
// handle the first "read" bytes of the buffer (index 0 to read-1)
}
} while (read != 0);
If you know that your buffer is enough for any stream, you can fill up the buffer and handle it afterwards:
buffer = new byte[4096];
int offset = 0;
do {
int read = DataStream.Read(buffer, offset, buffer.Length - offset);
offset += read;
} while (read != 0);
// handle the first "offset" bytes of the buffer (index 0 to offset-1)