Question

Hello guys im getting This error please see the attachment >> Index and count must refer to a location within the buffer. Parameter name: bytes

When im using debugger i dont get this error and everything goes fine i cannot understand what this error is

this is my server code :

 IPEndPoint ipEnd = new IPEndPoint(IPAddress.Any, 27015);
            Socket sck = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
            sck.Bind(ipEnd);
            sck.Listen(100);

            Socket clientSocket = sck.Accept();

            string[] fNames = new string[3];
            fNames[0] = "01.jpg";
            fNames[1] = "02.jpg";
            fNames[2] = "03.jpg";

            string filePath = "D:\\";

            byte[] FilesCount = BitConverter.GetBytes(fNames.Count());


            clientSocket.Send(FilesCount);

            for (int i = 0; i < fNames.Count(); i++)
            {
                byte[] fileNameByte = Encoding.ASCII.GetBytes(fNames[i]);
                byte[] fileData = File.ReadAllBytes(filePath + fNames[i]);
                byte[] clientData = new byte[4 + fileNameByte.Length + fileData.Length];
                byte[] fileNameLen = BitConverter.GetBytes(fileNameByte.Length);

                fileNameLen.CopyTo(clientData, 0);
                fileNameByte.CopyTo(clientData, 4);
                fileData.CopyTo(clientData, 4 + fileNameByte.Length);

                clientSocket.Send(clientData);
            }

            clientSocket.Close();

And Client:

   Socket clientSock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
        clientSock.Connect(IPAddress.Parse("46.49.70.30"), 27015);


        byte[] clientData = new byte[1024 * bt];
        string receivedPath = "D:/df/";

        byte[] FileQuantityByte = new byte[1024];
        clientSock.Receive(FileQuantityByte);
        int FileQuantity = BitConverter.ToInt32(FileQuantityByte, 0);

        for (int i = 0; i < FileQuantity; i++)
        {
            int receivedBytesLen = clientSock.Receive(clientData);

            int fileNameLen = BitConverter.ToInt32(clientData, 0);
            string fileName = Encoding.ASCII.GetString(clientData, 4, fileNameLen);

            //Console.WriteLine("Client:{0} connected & File {1} started received.", clientSock.RemoteEndPoint, fileName);

            BinaryWriter bWrite = new BinaryWriter(File.Open(receivedPath + fileName, FileMode.Append));
            bWrite.Write(clientData, 4 + fileNameLen, receivedBytesLen - 4 - fileNameLen);

            //Console.WriteLine("File: {0} received & saved at path: {1}", fileName, receivedPath);

            bWrite.Close();
        }

        clientSock.Close();

EDIT : http://imageshack.us/f/202/errbk.jpg/

Answer 1

The exception is telling exactly what the problem is: one of your parameters isn’t what you think it should be.

What is the length of clientData? What is the value of fileNameLen when you call Encoding.ASCII.GetString? What is the value of bt, which is used to initialize your clientData array?

If this doesn’t happen in the debugger, then add some code to output the values of clientData and fileNameLen before the call.

One problem is that clientSock.Receive might not get all of the data at once. If you’re sending an especially large file, it’s possible that clientSock.Receive will return without reading everything. As documentation for Socket.Receive says:

If you are using a connection-oriented Socket, the Receive method will read as much data as is available, up to the size of the buffer.

It’s possible that not all of the data is available yet, or that the buffer is smaller than the file size. To ensure that you get all of the data, you have to do this:

int totalBytesRead = 0;
int bytesRead = 0;
while ((bytesRead = clientSock.Receive(clientData, totalBytesRead,
    clientData.Length - totalBytesRead, SocketFlags.None)) != 0)
{
    totalBytesRead += bytesRead;
}

Receive will return 0 when there is no more data available. Only then can you be sure that you’ve received all of the data.