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C# file transfer with tcpclient and server

When I send a file with the code below, some data (small amout) is missing. The file size doess not match on the receiver side. Sending a regular string is fine so theres no connection issue here. Im just looking for a minimal improvement to fix the issue, I will add error checking etc later. Thanks! The code is mostly copied from some tutorial but i dont remember which though...
Client is the std .Net TcpClient class
Client.Client is it's socket
public void SendFile2(string fileName)
{
using (FileStream fs = File.OpenRead(fileName))
{
byte[] lenBytes = BitConverter.GetBytes((int)fs.Length);
Client.Client.Send(lenBytes);
byte[] buffer = new byte[1024];
int bytesRead;
fs.Position = 0;
while ((bytesRead = fs.Read(buffer, 0, 1024)) > 0)
Client.Client.Send(buffer, bytesRead, SocketFlags.None);
}
}
public bool ReceiveFile2(string fileName)
{
using (FileStream fs = File.Create(fileName))
{
byte[] lenBytes = new byte[4];
if (Client.Client.Receive(lenBytes) < 4)
return false;
long len = BitConverter.ToInt32(lenBytes, 0);
byte[] buffer = new byte[1024];
int bytesRead;
while ((bytesRead = Client.Client.Receive(buffer)) > 0)
fs.Write(buffer, 0, bytesRead);
return len == fs.Position;
}
}
SOLUTION:
public void SendFile(string fileName)
{
using (FileStream fs = File.OpenRead(fileName))
{
byte[] lenBytes = BitConverter.GetBytes((int)fs.Length);
Client.Client.Send(lenBytes);
byte[] buffer = new byte[1024];
int bytesRead;
fs.Position = 0;
while ((bytesRead = fs.Read(buffer, 0, 1024)) > 0)
Client.Client.Send(buffer, bytesRead, SocketFlags.None);
}
}
public bool ReceiveFile(string fileName)
{
using (FileStream fs = File.Create(fileName))
{
byte[] lenBytes = new byte[4];
if (Client.Client.Receive(lenBytes) < 4)
return false;
long len = BitConverter.ToInt32(lenBytes, 0);
byte[] buffer = new byte[1024];
int bytesRead;
// Changed from here
while (fs.Position < len)
{
bytesRead = Client.Client.Receive(buffer);
fs.Write(buffer, 0, bytesRead);
}
// To here
return len == fs.Position;
}
}

I think this line can be a problem.
if (Client.Client.Receive(lenBytes) < 4)
and
while ((bytesRead = Client.Client.Receive(buffer)) > 0)
You have two receives in your code.
So you drop first bytes.
That can explain the differences you see in files sizes.

C# Multi threaded Server

I have this client and server code.
Client:
namespace ClientTest
{
internal class Program
{
private static TcpClient client;
private static NetworkStream stream;
private static void Main(string[] args)
{
string temp;
client = new TcpClient("192.168.1.2",5052);
stream = client.GetStream();
Console.WriteLine(client.SendBufferSize);
while ((temp = Console.ReadLine()) != "exit")
{
Send(temp);
}
Thread one=new Thread(()=> SendFile(new FileInfo(#"1.doc")));
one.Start();
Thread two=new Thread(()=> SendFile(new FileInfo(#"2.docx")));
two.Start();
// Console.ReadKey(true);
}
public static void SendFile(FileInfo file)
{
stream = client.GetStream();
byte[] id = BitConverter.GetBytes((ushort)1);
byte[] size = BitConverter.GetBytes(file.Length);
byte[] fileName = Encoding.UTF8.GetBytes(file.Name);
byte[] fileNameLength = BitConverter.GetBytes((ushort)fileName.Length);
byte[] fileInfo = new byte[12 + fileName.Length];
id.CopyTo(fileInfo, 0);
size.CopyTo(fileInfo, 2);
fileNameLength.CopyTo(fileInfo, 10);
fileName.CopyTo(fileInfo, 12);
stream.Write(fileInfo, 0, fileInfo.Length); //Размер файла, имя
byte[] buffer = new byte[1024 * 32];
int count;
long sended = 0;
using (FileStream fileStream = new FileStream(file.FullName, FileMode.Open))
while ((count = fileStream.Read(buffer, 0, buffer.Length)) > 0)
{
stream.Write(buffer, 0, count);
sended += count;
Console.WriteLine("{0} bytes sended.", sended);
}
stream.Flush();
}
private static void Send(string message)
{
byte[] id = BitConverter.GetBytes((ushort)0);
byte[] msg = Encoding.UTF8.GetBytes(message);
byte[] msgLength = BitConverter.GetBytes((ushort)msg.Length);
byte[] fileInfo = new byte[12 + msg.Length];
id.CopyTo(fileInfo, 0);
msgLength.CopyTo(fileInfo, 10);
msg.CopyTo(fileInfo, 12);
stream.Write(fileInfo, 0, fileInfo.Length);
stream.Flush();
}
}
}
Server:
namespace Server_Test
{
class Server
{
static void Main(string[] args)
{
Server serv = new Server();
}
private TcpListener listener { get; set; }
private NetworkStream stream { get; set; }
public Server()
{
listener = new TcpListener(IPAddress.Parse("192.168.1.2"), 5052);
listener.Start();
new Thread(ListenForClients).Start();
}
private void ListenForClients()
{
while (true)
{
TcpClient client = this.listener.AcceptTcpClient();
new Thread(HandleClient).Start(client);
}
}
private void HandleClient(object tcpClient)
{
TcpClient client = (TcpClient)tcpClient;
while (client.Connected)
{
Recieve(client);
}
}
private void Recieve(TcpClient client)
{
byte[] buffer = new byte[client.ReceiveBufferSize];
try
{
stream = client.GetStream();
int bytesRead = stream.Read(buffer, 0, 12);
if (bytesRead == 0) return;
ushort id = BitConverter.ToUInt16(buffer, 0);
long len = BitConverter.ToInt64(buffer, 2);
ushort nameLen = BitConverter.ToUInt16(buffer, 10);
stream.Read(buffer, 0, nameLen);
string fileName = Encoding.UTF8.GetString(buffer, 0, nameLen);
if (id == 1)
{
using (BinaryWriter writer = new BinaryWriter(new FileStream(fileName, FileMode.Create)))
{
int recieved = 0;
while (recieved < len)
{
bytesRead = stream.Read(buffer, 0, client.ReceiveBufferSize);
recieved += bytesRead;
writer.Write(buffer, 0, bytesRead);
Console.WriteLine("{0} bytes recieved.", recieved);
}
}
Console.WriteLine("File length: {0}", len);
Console.WriteLine("File Name: {0}", fileName);
Console.WriteLine("Recieved!");
}
else
{
Console.WriteLine(fileName);
}
}
catch (Exception ex)
{
stream.Close();
client.Close();
Console.WriteLine(ex);
}
finally
{
stream.Flush();
}
}
}
}
The problem:i can't send 2 files in threads. If i send 1 file, server receives it and correctly saves.
What changes needed in this code to let client transfer 2 or more files and to let server receive it?
UDP. Added modified SendFile, but in doesn't work.
public static void SendFile(FileInfo file)
{
TcpClient client;
NetworkStream stream;
client = new TcpClient("192.168.1.2", 5052);
stream = client.GetStream();
byte[] id = BitConverter.GetBytes((ushort)1);
byte[] size = BitConverter.GetBytes(file.Length);
byte[] fileName = Encoding.UTF8.GetBytes(file.Name);
byte[] fileNameLength = BitConverter.GetBytes((ushort)fileName.Length);
byte[] fileInfo = new byte[12 + fileName.Length];
id.CopyTo(fileInfo, 0);
size.CopyTo(fileInfo, 2);
fileNameLength.CopyTo(fileInfo, 10);
fileName.CopyTo(fileInfo, 12);
stream.Write(fileInfo, 0, fileInfo.Length); //Размер файла, имя
byte[] buffer = new byte[1024 * 32];
int count;
long sended = 0;
using (FileStream fileStream = new FileStream(file.FullName, FileMode.Open))
while ((count = fileStream.Read(buffer, 0, buffer.Length)) > 0)
{
stream.Write(buffer, 0, count);
sended += count;
Console.WriteLine("{0} bytes sended.", sended);
}
}

On the client side, your two separate sending threads cannot share the same instance of client = new TcpClient("192.168.1.2",5052); to simultaneously send data. Each thread should have its own instance. Note, however, that it is fine for 2 client sockets to hit the same server-side IP:port simultaneously. It is just that the outbound port on the client-side has to be different between the 2 connections. When you create an additional outbound TCP connection on the client, the TcpClient will automatically use the next available outbound port.
For example, you could try something like the following:
internal class Program
{
private static void Main(string[] args)
{
SenderThreadClass stc1 = SenderThreadClass("192.168.1.2", 5052);
SenderThreadClass stc2 = SenderThreadClass("192.168.1.2", 5052);
Thread one = new Thread(()=> stc1.SendFile(new FileInfo(#"1.doc")));
one.Start();
Thread two = new Thread(()=> stc2.SendFile(new FileInfo(#"2.docx")));
two.Start();
}
}
public class SenderThreadClass
{
private TcpClient client;
private NetworkStream stream;
public SenderThreadClass(string serverIP, int serverPort)
{
client = new TcpClient(serverIP, serverPort);
stream = client.GetStream();
}
public void SendFile(FileInfo file)
{
byte[] id = BitConverter.GetBytes((ushort)1);
byte[] size = BitConverter.GetBytes(file.Length);
byte[] fileName = Encoding.UTF8.GetBytes(file.Name);
byte[] fileNameLength = BitConverter.GetBytes((ushort)fileName.Length);
byte[] fileInfo = new byte[12 + fileName.Length];
id.CopyTo(fileInfo, 0);
size.CopyTo(fileInfo, 2);
fileNameLength.CopyTo(fileInfo, 10);
fileName.CopyTo(fileInfo, 12);
stream.Write(fileInfo, 0, fileInfo.Length); //Размер файла, имя
byte[] buffer = new byte[1024 * 32];
int count;
long sended = 0;
using (FileStream fileStream = new FileStream(file.FullName, FileMode.Open))
while ((count = fileStream.Read(buffer, 0, buffer.Length)) > 0)
{
stream.Write(buffer, 0, count);
sended += count;
Console.WriteLine("{0} bytes sended.", sended);
}
stream.Flush();
}
}

decompress by gzip failed

i'm write one pair function too compress and decompress but decompress failed
this is my code
public static byte[] CompressByGzip( byte[] input ) {
using(var ims = new MemoryStream()) {
using(var gzip = new GZipStream(ims, CompressionMode.Compress)) {
gzip.Write(input, 0, input.Length);
return ims.ToArray();
}
}
}
public static byte[] DecompressByGzip( byte[] input ) {
using(var ims = new MemoryStream()) {
using(var gzip = new GZipStream(ims, CompressionMode.Decompress)) {
using(var outms = new MemoryStream()) {
ims.Write(input, 0, input.Length);
byte[] buf = new byte[bufLength];
int len=0;
while((len=gzip.Read(buf, 0, buf.Length))>0) {
outms.Write(buf, 0, len);
}
return outms.ToArray();
}
}
}
}
when i debug,i found the gzip can't read,it has inner Exception....
Length = “gzip.Length”引发了“System.NotSupportedException”类型的异常

Your compressed output CompressByGzip is wrong. You need to flush the gzip stream before converting to array. Move the return ... statement.
public static byte[] CompressByGzip( byte[] input )
{
using(var ims = new MemoryStream())
{
using(var gzip = new GZipStream(ims, CompressionMode.Compress))
{
gzip.Write(input, 0, input.Length);
}
return ims.ToArray();
}
}

Here is what you can do for .Net 4.5
Compress
public static byte[] Compress(byte[] data, CompressionLevel level = CompressionLevel.Fastest)
{
using (var memory = new MemoryStream())
{
using (var gzip = new GZipStream(memory, level, true))
{
gzip.Write(data, 0, data.Length);
}
return memory.ToArray();
}
}
Decompress
public static byte[] Decompress(byte[] byteData)
{
if (byteData == null)
throw new ArgumentNullException("byteData", #"inputData must be non-null");
using (var compressedMs = new MemoryStream(byteData))
{
using (var decompressedMs = new MemoryStream())
{
using (var gzs = new BufferedStream(new GZipStream(compressedMs, CompressionMode.Decompress), 4096))
{
gzs.CopyTo(decompressedMs);
}
return decompressedMs.ToArray();
}
}
}

ReadAsync get data from buffer

I've been banging my head around this for some while (and know it's something silly).
I'm downloading files with a ProgressBar which shows fine, but how do I get the data from the ReadAsync Stream to save?
public static readonly int BufferSize = 4096;
int receivedBytes = 0;
int totalBytes = 0;
WebClient client = new WebClient();
byte[] result;
using (var stream = await client.OpenReadTaskAsync(urlToDownload))
{
byte[] buffer = new byte[BufferSize];
totalBytes = Int32.Parse(client.ResponseHeaders[HttpResponseHeader.ContentLength]);
for (;;)
{
result = new byte[stream.Length];
int bytesRead = await stream.ReadAsync(buffer, 0, buffer.Length);
if (bytesRead == 0)
{
await Task.Yield();
break;
}
receivedBytes += bytesRead;
if (progessReporter != null)
{
DownloadBytesProgress args =
new DownloadBytesProgress(urlToDownload, receivedBytes, totalBytes);
progessReporter.Report(args);
}
}
}
I was trying via the result var, but that is obviously wrong. I'd appreciate any pointers on this long Sunday afternoon.

The content that was downloaded is inside your byte[] buffer variable:
int bytesRead = await stream.ReadAsync(buffer, 0, buffer.Length);
From Stream.ReadAsync:
buffer:
Type: System.Byte[]
The buffer to write the data into.
You never use your result variable at all. Not sure why its there.
Edit
So the problem is how to read the full content of your stream. You can do the following:
public static readonly int BufferSize = 4096;
int receivedBytes = 0;
WebClient client = new WebClient();
using (var stream = await client.OpenReadTaskAsync(urlToDownload))
using (MemoryStream ms = new MemoryStream())
{
var buffer = new byte[BufferSize];
int read = 0;
totalBytes = Int32.Parse(client.ResponseHeaders[HttpResponseHeader.ContentLength]);
while ((read = await stream.ReadAsync(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, read);
receivedBytes += read;
if (progessReporter != null)
{
DownloadBytesProgress args =
new DownloadBytesProgress(urlToDownload, receivedBytes, totalBytes);
progessReporter.Report(args);
}
}
return ms.ToArray();
}
}

The data you read should be in the buffer array. Actually the beginning bytesRead bytes of the array. Check ReadAsync method on MSDN.

compressing and decomressing in .net endsup with an decompressed array of zero's

I'm trying to compress and decompress a memory stream to send it over an tcp connection.
In the following code snap I do do the decompressing right after compressing to get it working first.
What ever I do I end up with a devompressed buffer wit all zero's and in the line
int read = Decompress.Read(buffie, 0, buffie.Length);
it seems that 0 bytes are read.
Does anyone has a clue what is wrong?
bytesRead = ms.Read(buf, 0, i);
MemoryStream partialMs = new MemoryStream();
GZipStream gZip = new GZipStream(partialMs, CompressionMode.Compress);
gZip.Write(buf, 0, buf.Length);
partialMs.Position = 0;
byte[] compressedBuf = new byte[partialMs.Length];
partialMs.Read(compressedBuf, 0, (int)partialMs.Length);
partialMs.Close();
byte[] gzBuffer = new byte[compressedBuf.Length + 4];
System.Buffer.BlockCopy(compressedBuf, 0, gzBuffer, 4, compressedBuf.Length);
System.Buffer.BlockCopy(BitConverter.GetBytes(buf.Length), 0, gzBuffer, 0, 4);
using (MemoryStream mems = new MemoryStream())
{
int msgLength = BitConverter.ToInt32(gzBuffer, 0);
byte[] buffie = new byte[msgLength];
mems.Write(gzBuffer, 4, gzBuffer.Length - 4);
mems.Flush();
mems.Position = 0;
using (GZipStream Decompress = new GZipStream(mems, CompressionMode.Decompress, true))
{
int read = Decompress.Read(buffie, 0, buffie.Length);
Decompress.Close();
}
}

Your implementation could use some work. there seems to be some confusion as to which streams should be used where. here is a working example to get you started..
see user content at the bottom of this MSDN page
var original = new byte[65535];
var compressed = GZipTest.Compress(original);
var decompressed = GZipTest.Decompress(compressed);
using System.IO;
using System.IO.Compression;
public class GZipTest
{
public static byte[] Compress(byte[] uncompressedBuffer)
{
using (var ms = new MemoryStream())
{
using (var gzip = new GZipStream(ms, CompressionMode.Compress, true))
{
gzip.Write(uncompressedBuffer, 0, uncompressedBuffer.Length);
}
byte[] compressedBuffer = ms.ToArray();
return compressedBuffer;
}
}
public static byte[] Decompress(byte[] compressedBuffer)
{
using (var gzip = new GZipStream(new MemoryStream(compressedBuffer), CompressionMode.Decompress))
{
byte[] uncompressedBuffer = ReadAllBytes(gzip);
return uncompressedBuffer;
}
}
private static byte[] ReadAllBytes(Stream stream)
{
var buffer = new byte[4096];
using (var ms = new MemoryStream())
{
int bytesRead = 0;
do
{
bytesRead = stream.Read(buffer, 0, buffer.Length);
if (bytesRead > 0)
{
ms.Write(buffer, 0, bytesRead);
}
} while (bytesRead > 0);
return ms.ToArray();
}
}
}

You're not closing the GzipStream you're writing to, so it's probably all buffered. I suggest you close it when you're done writing your data.
By the way, you can get the data out of a MemoryStream much more easily than your current code: use MemoryStream.ToArray.