Transferring files through sockets (bir and small sized) - c#

Hello I'm trying to implement a server and client couple that can transfer files of any kind and any size but there is a problem I somehow corrupt files. I tried lots of methods but can't figure it out. So basicly I can connect ,I can understand which file does client want, and can send it through sockets. When I try to open that file it shows me an error message(Tried winrar, mp4, avi files) Here is my code:
//Server
private void Receive(string receivedFileName, string fileSize)
{
try
{
int receivedBytesLen = 0;
byte[] incomingFile = new byte[int.Parse(fileSize)];
activity.AppendText("Preparing to download... \n");
while (incomingFile != null && int.Parse(fileSize) > receivedBytesLen)
{
tempSocket.Receive(incomingFile);
receivedBytesLen = incomingFile.Length;
int fileNameLen = BitConverter.ToInt32(incomingFile, 0);
File.WriteAllBytes(fileDir + "//" + receivedFileName, incomingFile);
}
activity.AppendText("File saved to " + fileDir + "\n");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
//////////////////////////////////////////////////////////////////////
//server option 2
private void Receive(string receivedFileName, string fileSize)
{
try
{
byte[] incomingFile = new byte[10124 * 5000];
activity.AppendText("Preparing to download... \n");
BinaryWriter bWrite = new BinaryWriter(File.Open(folderBrowserDialog1.SelectedPath + "//" + receivedFileName, FileMode.Append));
int receivedBytesLen = tempSocket.Receive(incomingFile, incomingFile.Length, 0);
int fileNameLen = BitConverter.ToInt32(incomingFile, 0);
//string fileName = Encoding.UTF8.GetString(incomingFile, 4, fileNameLen);
//bWrite.Write(incomingFile, 4 + fileNameLen, receivedBytesLen - 4 - fileNameLen);
while (receivedBytesLen > 0)
{
receivedBytesLen = tempSocket.Receive(incomingFile, incomingFile.Length, 0);
if (receivedBytesLen == 0)
{
bWrite.Close();
}
else
{
bWrite.Write(incomingFile, 0, receivedBytesLen);
}
}
activity.AppendText("File saved to " + fileDir + "\n");
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
/////////////////////////////////////////////////////////////////////
//client
private void Upload_Click(object sender, EventArgs e)
{//Uploads selected file after clicking upload button.
try
{
if (clientSocket.Connected)
{
byte[] buffer = new byte[1024];
byte[] sendingFile = null;
sendingFile = File.ReadAllBytes(openFileDialog1.FileName);
FileInfo f = new FileInfo(openFileDialog1.FileName);
string fileSize = f.Length.ToString();
buffer = Encoding.Default.GetBytes(getUserName.Text + "Upload" + openFileDialog1.SafeFileName + "size" + fileSize + "end");
clientSocket.Send(buffer);
activityLog.AppendText("Sending File \n");
int bytesToBeSent = sendingFile.Length;
int bytesActuallySent = 0;
while(bytesActuallySent < bytesToBeSent){
bytesActuallySent += clientSocket.Send(sendingFile, bytesActuallySent, bytesToBeSent -bytesActuallySent, 0);
}
activityLog.AppendText("File Sent.\n");
}
}
catch(Exception ex){
MessageBox.Show(ex.Message);
}
}

server option #2 is better. But there are some improvements
socket receive buffer is limited decided by OS, generally is 8192
use FileStream in client and server and do not forget to close filestream after file download
client:
FileStream fileStream = new FileStream(filePath, FileMode.Open)
byte[] buff = new byte[8192];
do
{
bytesRead = fileStream.Read(buff, 0, buff.Length);
sock.send(dataSock, buff, bytesRead);
}while (bytesRead > 0);
fileStream.close();
server:
FileStream fileStream = new FileStream(filePath, FileMode.Open)
do
{
bytesRead = sock.receive(buff, 0, buff.Lenght);
fileStream.Write(buff, 0, bytesRead );
}while (bytesRead > 0);
fileStream.close();

In order to satisfy ANY sized file you need an option #3, one that reads a block of bytes til all bytes are received, your option #1 wouldn't do so well on a 3 GIG file running on 2 GIG box...
Here is a link: http://www.yoda.arachsys.com/csharp/readbinary.html
I like option #2 from this link.
However in the example they write to a memoryStream, you should write to a filestream, the target file.

Related

Transformation an image file in tcp/ip

I convert image file into a byte array and packetize it to 14-byte packets and send it via SerialPortEventHandler. on the other hand, in reciever part I lost some packets and when I generate recieved byte array in a new image file, the rest of the image, after the lost packet, shifted incorrectly, I have replaced lost packets with zero. while this works with text file perfectly. This is my code in client and server side:
client
_file = ofile.ConvertFileToByte(txtFileName.Text);
for (int k = 0; k < Configuration.PacketNumberInFrame; k++)
{
((BackgroundWorker)sender).ReportProgress((j * Configuration.PacketNumberInFrame + i) * 100 / Configuration.FileCount);
if (i + _numberOfByte <= Configuration.FileCount)
_packet = _file.SubArray(i, _numberOfByte);
}
//send packet
...
Server
try
{
while (true)
{
size = port.BytesToRead;
if (size >= 18)
break;
}
byte[] packet = new byte[size];
var str2 = port.Read(packet, 0, size);
if (System.Text.Encoding.Default.GetString(packet).Contains(Configuration.EndKeyByte) && !endFlag)
EndRecieving();
else
Extract(packet);
}
catch
(Exception ex)
{
MessageBox.Show(ex.Message);
}
}
public Extract(packet)
{
Recieve_Data.Add( packet);
}
public EndRecieving()
{
for(int i=0;i< arrayResult.AddRange(packetData);i++)
{
arrayResult.AddRange(packetData);
}
string filePath = Configuration.LogFilePath + "\\CreatedFile-" + "."filePrefix.ToLower();
var stream = new FileStream(filePath,
FileMode.Create,
FileAccess.ReadWrite);
FileData oFile = new FileData();
stream.Write(result, 0, result.Length);
stream.Close();
}

Download a file with .net compact and C#

I am re-developing an app for a scanner used for stocktakes to allow it to work while offline. In order to do so, I need to be able to download a file from a laptop which is acting as a server. I got to a point at which it works, but only downloads that are of size 9.53mb max. How can I tweak the code to allow for larger files. I would need to allow for a maximum size of around 30mb.
Here is my code:
try
{
string full_url = App.prouductUrl + App.stStocktakeId + ".db";
HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(full_url);
httpRequest.Credentials = CredentialCache.DefaultCredentials;
HttpWebResponse httpResponse = (HttpWebResponse)httpRequest.GetResponse();
System.IO.Stream dataStream = httpResponse.GetResponseStream();
// Dim str As Stream = cdsMobileLibrary2.http_download.getfile(filename)
//50 meg
byte[] inBuf = new byte[10000001];
int bytesToRead = Convert.ToInt32(inBuf.Length);
int bytesRead = 0;
while (bytesToRead > 0)
{
int n = dataStream.Read(inBuf, bytesRead, bytesToRead);
if (n == 0)
{
break; // TODO: might not be correct. Was : Exit While
}
bytesRead += n;
bytesToRead -= n;
}
FileStream fstr = new FileStream(#"\productdb\" + App.stStocktakeId + ".db", FileMode.OpenOrCreate, FileAccess.Write);
fstr.Write(inBuf, 0, bytesRead);
dataStream.Close();
fstr.Close();
string size = loginRes.getFromJSON("size");
FileInfo fi = new FileInfo(#"\productdb\" + App.stStocktakeId + ".db");
MessageBox.Show("File Size is:" + fi.Length + "Compared to:" + size);
}
catch { }

Reading Data from Network Stream in TCP Listener

I'm having a network stream which is having filename and filedata in it. I'm sending files in some chunks and each chunk carries the filename for easy identification. Can you please help me in reading the network stream properly and writing all of the data to the file stream.
I seem to miss few bytes when i write the data from network stream.
Say for example filename length will be in oth index and filename will start from 4th index.
Client:
int NoOfPackets = Convert.ToInt32
(Math.Ceiling((Convert.ToDouble(Fs.Length))/ Convert.ToDouble(BufferSize)));
int TotalLength = (NoOfPackets *4+fileNameByte.Length) +(int)Fs.Length, CurrentPacketLength, counter = 0;
netstream1 = client.GetStream();
for (int i = 0; i < NoOfPackets+1 ; i++)
{
if (TotalLength > BufferSize)
{
CurrentPacketLength = BufferSize;
TotalLength = TotalLength - CurrentPacketLength;
}
else
CurrentPacketLength = TotalLength;
SendingBuffer = new byte[CurrentPacketLength];
fileNameLength.CopyTo(SendingBuffer, 0);
fileNameByte.CopyTo(SendingBuffer, 4);
Fs.Read(SendingBuffer, 4 + fileNameByte.Length, CurrentPacketLength - (4 + fileNameByte.Length));
netstream1.Write(SendingBuffer, 0, SendingBuffer.Length);
netstream1.Flush();
}
Listener Code:
client = Listener.AcceptTcpClient();
client.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, true);
//client.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.Linger, true);
client.Client.LingerState = new LingerOption(true, 300);
client.Client.SendTimeout = 300000;
client.Client.ReceiveTimeout = 300000;
client.NoDelay = true;
NetworkStream netstream = client.GetStream();
MemoryStream ms = new MemoryStream();
bool first = true;
string fullPath = "";
byte[] RecData = new byte[512000];
while ((RecBytes = netstream.Read
(RecData, 0, RecData.Length)) > 0)
{
int fileNameLen = RecData[0];
if (fileNameLen > 0 && first)
{
string name1 = "", name2 = "";
first = false;
name1 = Encoding.UTF8.GetString(RecData, 4, fileNameLen);
name2 = name1;
string folderName = "";
if (name2.Contains("\\"))
{
folderName = name2.Substring(0, name2.LastIndexOf("\\"));
if (!Directory.Exists("D:\\123\\" + folderName))
Directory.CreateDirectory("D:\\123\\" + folderName);
}
if (folderName != "")
fullPath = "D:\\123\\" + folderName + "\\" + name2.Substring(name2.LastIndexOf("\\") + 1);
else
fullPath = "D:\\123\\" + name2.Substring(name2.LastIndexOf("\\") + 1);
}
if (!File.Exists(fullPath))
{
//file = new FileStream(fullPath, FileMode.OpenOrCreate, FileAccess.Write);
while (true)
{
try
{
using (FileStream file = new FileStream(fullPath, FileMode.OpenOrCreate, FileAccess.Write))
{
if (RecBytes - (4 + fileNameLen) > 0)
file.Write(RecData, 4 + fileNameLen, RecBytes - (4 + fileNameLen));
break;
}
}
catch (IOException)
{
Thread.Sleep(20);
}
}
//using (file = File.Create(fullPath))
//{
// file.Write(data, 4 + fileNameLen, (int)data.Length - (4 + fileNameLen));
//}
}
else
{
while (true)
{
try
{
using (FileStream file = new FileStream(fullPath, FileMode.Append, FileAccess.Write))
{
if (RecBytes - (4 + fileNameLen) > 0)
file.Write(RecData, 4 + fileNameLen, RecBytes - (4 + fileNameLen));
break;
}
}
catch (IOException)
{
Thread.Sleep(20);
}
}
}
}
ms.Close();
netstream.Close();
client.Close();
even though you are as vague as anyone can be, still I would suggest that you create a structure so that serialization and de-serialization of data could be done in a known format!! and data loss could be avoided!!
Again if your approach is known it would be great help in answering your question.

Sending strings and File from Android Client to C# server

I am trying to send files with a bunch of strings from Android client to C# server. The strings, among other things, will also contain details with regards to the file being sent eg: File Size, File Name, etc. The issue I am having is that all the file bytes is not received thus the original file cannot be reconstructed at the destination even though I can properly retrieve all the strings.
My C# Server Code
while (true)
{
Socket socket = listener.AcceptSocket();
setStatus(socket.RemoteEndPoint + " Connected");
try
{
// Open the stream
NetworkStream stream = new NetworkStream(socket);
System.IO.StreamReader sr = new StreamReader(stream);
//Get string data
//********************************************
Teststr = sr.ReadLine();
setStatus(Teststr);
FileSize = sr.ReadLine();
long fileSizeLong = Convert.ToInt64(FileSize);
int length = (int)fileSizeLong;
setStatus("File size: " + length + " bytes");
//********************************************
//read bytes to buffer
byte[] buffer = new byte[length];
int toRead = (int)length;
int read = 0;
while (toRead > 0)
{
int noChars = stream.Read(buffer, read, toRead);
read += noChars;
toRead -= noChars;
}
setStatus("File Recieved. Total bytes: " + Convert.ToString(buffer.Length));
setStatus("Saving File");
String recievedPath = "C:\\Test\\";
BinaryWriter bWrite = new BinaryWriter(File.Open(recievedPath + "Test.png", FileMode.Create));
bWrite.Write(buffer);
setStatus("File Saved to: " + recievedPath);
bWrite.Flush();
bWrite.Close();
stream.Flush();
stream.Close();
}
catch (Exception e)
{
setStatus(e.Message);
}
setStatus("Disconnected");
socket.Close();
}
My Android Client Code
File file = new File(configstr[2]); //create file instance
try {
client = new Socket(configstr[0], Integer.valueOf(configstr[1]));
//Read file
fileInputStream = new FileInputStream(file);
outputStream = client.getOutputStream();
//Output database details to stream
//*****************************************
//Holds the string before conversion to bytes
String text = "";
text = "Test\n";
outputStream.write(text.getBytes());
text = String.valueOf(file.length()) + "\n";
outputStream.write(text.getBytes());
//*****************************************
outputStream.flush();
ByteArrayOutputStream bos = new ByteArrayOutputStream();
byte[] b = new byte[1024];
int bytesRead = 0;
while ((bytesRead = fileInputStream.read(b)) != -1) {
bos.write(b, 0, bytesRead);
}
byte[] bytes = bos.toByteArray();
outputStream.write(bytes);
outputStream.flush();
return true;
} catch (UnknownHostException e) {
e.printStackTrace();
return false;
} catch (IOException e) {
e.printStackTrace();
return false;
}
NOTE: The code works well if I only send one string, eg: If I only send file size.
Any better way of getting this to work as I am trying to send many strings through the stream as well as binary data from the file.
BufferedWriter with flush() at the end of every write() solved the issue for me.

form turn to not responding after downloading a file from server

Its a very weird thing.
I created a client and a server to upload and download files. When uploading I can upload a lot of files without a problem but when I download a file the client for turn to not responding and doesn't show MessageBox.show("Downloaded"); its the first tie to see this :D.
The code that make the problem when used :
private void button3_Click(object sender, EventArgs e)
{
try
{
String fileToDownload = filePathDownload.Text;
TcpClient clientSocket = new TcpClient(serverIPDownload.Text, 8880);
NetworkStream networkStream = clientSocket.GetStream();
ASCIIEncoding asci = new ASCIIEncoding();
byte[] b = asci.GetBytes(fileToDownload + "?");
byte[] bb = asci.GetBytes("Download?");
int thisRead = 0;
int blockSize = 1024;
Byte[] dataByte = new Byte[blockSize];
networkStream.Write(bb, 0, bb.Length);
networkStream.Flush();
networkStream.Write(b, 0, b.Length);
networkStream.Flush();
using (FileStream fileStream = new FileStream(
"C:/Users/Laptop/Documents/Downloads/" + fileToDownload,
FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None))
{
while (true)
{
thisRead = networkStream.Read(dataByte, 0, blockSize);
fileStream.Write(dataByte, 0, thisRead);
if (thisRead == 0) break;
}
MessageBox.Show("File Downloaded");
fileStream.Close();
}
}
catch (Exception ex) { MessageBox.Show(ex.Message); }
}
Thanks. This maybe off topic but its the problem I faced.
Your code appears to be ok, so I suspect the problem is in the Download method you are reading from.
Also, I would personally move the loop termination (if (thisRead == 0) break;) before the fileStream.Write statement.
And for production code, I would add some sort of timeout limit so that you don't end up in an infinite loop.

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