Re: Can someone help me

Thx first,
the code is base on the book but i change a little bit, the example from 

the book is only support text file, but i want to also support binary file.
actually, i am new to c#, and i haven't many programming experience

One thing which concerns me is that your OnReadComplete assumes that
whenever you've successfully read a piece of data, that it must contain
a complete filename. What happens if a long filename is sent which is
split over multiple packets, for instance

How can i handle this problem? I am sorry about my English is not very good,and Tnank again


the origianl code is below

using System;
using System.Net.Sockets;
using System.Text;
using System.IO;
// get a file name from the client
// open the file and send the
// contents from the server to the client
public class AsynchNetworkFileServer
{
	class ClientHandler
	{
		// constructor
		public ClientHandler(
			Socket socketForClient )
		{
			// initialize member variable
			socket = socketForClient;
			// initialize buffer to hold
			// contents of file
			
				buffer = new byte[256];
			// create the network stream
			networkStream =
				new NetworkStream(socketForClient);
			// set the file callback for reading
			// the file
			myFileCallBack =
				new AsyncCallback(this.OnFileCompletedRead);
			// set the callback for reading from the
			// network stream
			callbackRead =
				new AsyncCallback(this.OnReadComplete);
			// set the callback for writing to the
			// network stream
			callbackWrite =
				new AsyncCallback(this.OnWriteComplete);
		}
		// begin reading the string from the client
		public void StartRead( )
		{
			// read from the network
			// get a filename
			networkStream.BeginRead(
				buffer, 0, buffer.Length,
				callbackRead, null);
		}
		// when called back by the read, display the string
		// and echo it back to the client
		private void OnReadComplete( IAsyncResult ar )
		{
			int bytesRead = networkStream.EndRead(ar);
			// if you got a string
			if( bytesRead > 0 )
			{
				// turn the string to a file name
				string fileName =
					System.Text.Encoding.ASCII.GetString(
					buffer, 0, bytesRead);
				// update the console
				Console.Write(
					"Opening file {0}", fileName);
				// open the file input stream
				inputStream =
					File.OpenRead(fileName);
				// begin reading the file
				inputStream.BeginRead(
					buffer, // holds the results
					0, // offset
					buffer.Length, // BufferSize
					myFileCallBack, // call back delegate
					null); // local state object
			
					}
			else
			{
				Console.WriteLine( "Read connection dropped");
				networkStream.Close( );
				socket.Close( );
				networkStream = null;
				socket = null;
			}
		}
		// when you have a buffer-full of the file
		void OnFileCompletedRead(IAsyncResult asyncResult)
		{
			int bytesRead =
				inputStream.EndRead(asyncResult);
			// if you read some file
			if (bytesRead > 0)
			{
				// write it out to the client
				networkStream.BeginWrite(
					buffer, 0, bytesRead, callbackWrite, null);
			}
		}
		// after writing the string, get more of the file
		private void OnWriteComplete( IAsyncResult ar )
		{
			networkStream.EndWrite(ar);
			Console.WriteLine( "Write complete");
			// begin reading more of the file
			inputStream.BeginRead(
				buffer, // holds the results
				0, // offset
				buffer.Length, // (BufferSize)
				myFileCallBack, // call back delegate
				null); // local state object
		}
		private const int BufferSize = 256;
		private byte[] buffer;
		private Socket socket;
		private NetworkStream networkStream;
		private Stream inputStream;
		private AsyncCallback callbackRead;
		private AsyncCallback callbackWrite;
		private AsyncCallback myFileCallBack;
	}
	public static void Main( )
	{
		AsynchNetworkFileServer app =
			new AsynchNetworkFileServer( );
		
			app.Run( );
	}
	private void Run( )
	{
		// create a new TcpListener and start it up
		// listening on port 65000
		TcpListener tcpListener = new TcpListener(65000);
		tcpListener.Start( );
		// keep listening until you send the file
		for (;;)
		{
			// if a client connects, accept the connection
			// and return a new socket named socketForClient
			// while tcpListener keeps listening
			Socket socketForClient =
				tcpListener.AcceptSocket( );
			if (socketForClient.Connected)
			{
				Console.WriteLine("Client connected");
				ClientHandler handler =
					new ClientHandler(socketForClient);
				handler.StartRead( );
			}
		}
	}
}
.

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