using System;
using System.IO;
using System.Net;
using System.Net.Sockets;
namespace Network
{
///
/// FtpClient class performs the actions of a simple ftp client
///
public class FtpClient : AFtpClient
{
private bool bConnectionOpen = false;
private bool bStreamReady = false;
private string m_sUsername = "";
private string m_sPassword = "";
private string m_sHost = "";
private int m_iPort = 21;
private TcpClient m_tcpClient = null;
private NetworkStream m_commandStream = null;
private StreamReader m_comRead = null;
///
/// Initializes the ftp client
///
/// Hostname of the remote machine
/// User name of the remote machine account
/// Password of the remote machine account
public FtpClient(string sHost, string sUser, string sPassword)
{
m_sHost = sHost;
m_sUsername = sUser;
m_sPassword = sPassword;
}
///
/// Initializes the ftp client
///
/// Hostname of the remote machine
public FtpClient(string sHost)
{
m_sHost = sHost;
}
///
/// Initializes the ftp client
///
/// Hostname of the remote machine
/// Port of the remote machine
public FtpClient(string sHost, int iPort)
{
m_sHost = sHost;
m_iPort = iPort;
}
public FtpClient()
{
}
///
/// Username of the remote machine account
///
public override string Username
{
get
{
return m_sUsername;
}
set
{
m_sUsername = value;
}
}
///
/// Password of the remote machine account
///
public override string Password
{
get
{
return m_sPassword;
}
set
{
m_sPassword = value;
}
}
///
/// Hostname of the remote machine
///
public override string Host
{
get
{
return m_sHost;
}
set
{
m_sHost = value;
}
}
///
/// FTP port of the remote machine. This property is set to 21 by default
///
public override int Port
{
get
{
return m_iPort;
}
set
{
m_iPort = value;
}
}
///
/// Opens the connection to the remote machine
///
public override void Open()
{
if (bConnectionOpen)
{
throw new FtpClientException(1,"Connection already open");
}
try
{
m_tcpClient = new TcpClient(m_sHost, m_iPort);
m_tcpClient.ReceiveBufferSize = 4096; // alocate a 4kb buffer (for extra large MOTDs)
}
catch (SocketException e)
{
throw new FtpClientException(e.ErrorCode,"FtpClient cannot establish a connection");
}
m_commandStream = m_tcpClient.GetStream(); // get the command stream
m_comRead = new StreamReader(m_commandStream); // now we can read the stream
//m_comWrite = new StreamWriter(m_commandStream,System.Text.Encoding.ASCII); // and write to it(hmmm .. in beta 2 that is
// we just successfully connected so the server welcomes us with a 220 response
string sOut = m_comRead.ReadLine();
if (sOut.Substring(0,3) != "220") { throw new FtpClientException(3, "Unrecognized response on connect"); }
WriteToStream("USER " + m_sUsername); // send our user name
// the server must reply with 331
sOut = m_comRead.ReadLine();
if (sOut.Substring(0,3) != "331") { throw new FtpClientException(4, "User does not exist on the remote machine, or anonymous access is blocked"); }
WriteToStream("PASS " + m_sPassword); // send our password
sOut = m_comRead.ReadLine();
// the server must reply with 230, which is a successful login
// after that the server's MOTD/disclaimer might follow, so we
// will async-read the stream to the end after we get the first response line
// to the end of it, this is needed for really slow connections(this still happens:)
// because we can't issue commands to the server until it sends us everything
if (sOut.Substring(0,3) != "230") { throw new FtpClientException(5, "Password is incorrect for this user"); }
if (m_commandStream.DataAvailable)
{
m_commandStream.BeginRead(new byte[4096],0,4096,new AsyncCallback(ReadEnd),null);
}
else
{
bStreamReady = true;
}
bConnectionOpen = true;
}
///
/// Sets the current remote directory
///
/// Directory name
public override void SetCurrentDirectory(string sDirectory)
{
if (!bConnectionOpen)
{
throw new FtpClientException(6,"Connection not open");
}
while (!bStreamReady)
{
// wait for the server to become ready for more commands
System.Threading.Thread.Sleep(200);
}
WriteToStream("CWD " + sDirectory); // send the command to change directory
string sOut = m_comRead.ReadLine();
// server must reply with 250, else the directory does not exist
if (sOut.Substring(0,3) != "250") { throw new FtpClientException(7, "Remote directory does not exist"); }
}
///
/// Gets a file from the ftp server, if sRemoteFilename contains a mask only the
/// first file matching the mask is received.
///
/// Full filename of the local file [Path+Name]
/// Remote file name
/// Transfer mode constant
public override void ReceiveFile(string sLocalFilename, string sRemoteFilename, TransferMode mode)
{
// create a new file
FileStream fStream = new FileStream(sLocalFilename,FileMode.Create,FileAccess.ReadWrite,FileShare.Read,1024,false);
string sOut = null;
// set mode
switch (mode)
{
case TransferMode.Ascii:
{
WriteToStream("TYPE A");
sOut = m_comRead.ReadLine(); // consume the return message
break;
}
case TransferMode.Binary:
{
WriteToStream("TYPE I");
sOut = m_comRead.ReadLine(); // consume the return message
break;
}
}
// get a list of IP addresses for this machine
IPHostEntry ipThis = Dns.GetHostByName(Dns.GetHostName());
Random r = new Random();
int port = 0;
bool bIPFound = false;
// we will try all IP addresses assigned to this machine
// the first one that the remote machine likes will be chosen
for(int i=0;i0)
{
bytesRead = xfer.Receive(bData,0,1024,SocketFlags.None);
fStream.Write(bData,0,bytesRead);
}
fStream.Close();
xfer.Shutdown(SocketShutdown.Both);
xfer.Close();
conn.Stop();
conn = null;
xfer = null;
fStream = null;
sOut = m_comRead.ReadLine(); // consume the "226 Transfer Complete" response
}
catch (Exception e)
{
throw e; // propagate the exception
}
}
///
/// Puts a file to the ftp server, if sRemoteFilename contains a mask only the
/// first file matching the mask is received.
///
/// Full filename of the local file [Path+Name]
/// Remote file name
/// Transfer mode constant
public override void SendFile(string sLocalFilename, string sRemoteFilename, TransferMode mode)
{
// create a new file
FileStream fStream = new FileStream(sLocalFilename,FileMode.Open,FileAccess.Read,FileShare.Read,1024,false);
string sOut = null;
// set mode
switch (mode)
{
case TransferMode.Ascii:
{
WriteToStream("TYPE A");
sOut = m_comRead.ReadLine(); // consume the return message
break;
}
case TransferMode.Binary:
{
WriteToStream("TYPE I");
sOut = m_comRead.ReadLine(); // consume the return message
break;
}
}
// get a list of IP addresses for this machine
IPHostEntry ipThis = Dns.GetHostByName(Dns.GetHostName());
Random r = new Random();
int port = 0;
bool bIPFound = false;
// we will try all IP addresses assigned to this machine
// the first one that the remote machine likes will be chosen
for(int i=0;i0)
{
bytesRead = fStream.Read(bData,0,1024);
xfer.Send(bData,0,bytesRead,SocketFlags.None);
}
fStream.Close();
xfer.Shutdown(SocketShutdown.Both);
xfer.Close();
conn.Stop();
conn = null;
xfer = null;
fStream = null;
sOut = m_comRead.ReadLine(); // consume the "226 Transfer Complete" response
}
catch (Exception e)
{
throw e; // propagate the exception
}
}
///
/// Closes the connection to remote host
///
public void Close()
{
m_comRead.Close();
m_commandStream.Close();
m_tcpClient.Close();
bConnectionOpen = false;
bStreamReady = false;
}
private void WriteToStream(string command)
{
// this is interesting, in Beta 2 of .NET I was able to use the
// StreamWriter to write to the stream. Now I am not, the stream becomes
// blocked, so this method writes a byte array directly to the stream
m_commandStream.Write(System.Text.Encoding.ASCII.GetBytes(command+"\n"),0,command.Length+1);
}
private void ReadEnd(IAsyncResult ar)
{
bStreamReady = true;
}
}
}
