改进后的FTPFactory

转载自网上广为流传的一个C#写的FTP类

原作者：Jaimon Mathew

稍作修改者：Sunjoy  at CCNU

不是我自己写的。你可以在google上搜FTPFactory，就会得到答案了。
我对这个库做了三个地方的修改：
1、支持汉字
2、添加了GetSubdirs方法，原来的库不区分文件与子文件夹。
3、在其中适当的地方加入了延时，原来的库在打开有的FTP的时候会永久阻塞。

using System;
using System.Net;
using System.IO;
using System.Text;
using System.Net.Sockets;
using System.Threading;
using System.Collections;
namespace softplib
{

 public class FTPFactory
 {

  private string
   remoteHost,remotePath,remoteUser,remotePass,mes;
  private int remotePort,bytes;
  private Socket clientSocket;

  private int retValue;
  private Boolean debug;
  private Boolean logined;
  private string reply;

  private static int BLOCK_SIZE = 10240;

  Byte[] buffer = new Byte[BLOCK_SIZE];
  Encoding ASCII = Encoding.Default;
  private void delay(){
   Thread.Sleep(10);
  }

  public FTPFactory()
  {

   remoteHost  = "localhost";
   remotePath  = ".";
   remoteUser  = "anonymous";
   remotePass  = "[e-mail]";
   remotePort  = 21;
   debug     = false;
   logined    = false;

  }

  ///
  /// Set the name of the FTP server to connect to.
  ///
  /// Server name
  public void setRemoteHost(string remoteHost)
  {
   this.remoteHost = remoteHost;
  }

  ///
  /// Return the name of the current FTP server.
  ///
  /// Server name
  public string getRemoteHost()
  {
   return remoteHost;
  }

  ///
  /// Set the port number to use for FTP.
  ///
  /// Port number
  public void setRemotePort(int remotePort)
  {
   this.remotePort = remotePort;
  }

  ///
  /// Return the current port number.
  ///
  /// Current port number
  public int getRemotePort()
  {
   return remotePort;
  }

  ///
  /// Set the remote directory path.
  ///
  /// The remote directory path
  public void setRemotePath(string remotePath)
  {
   this.remotePath = remotePath;
  }

  ///
  /// Return the current remote directory path.
  ///
  /// The current remote directory path.
  public string getRemotePath()
  {
   return remotePath;
  }

  ///
  /// Set the user name to use for logging into the remote server.
  ///
  /// Username
  public void setRemoteUser(string remoteUser)
  {
   this.remoteUser = remoteUser;
  }

  ///
  /// Set the password to user for logging into the remote server.
  ///
  /// Password
  public void setRemotePass(string remotePass)
  {
   this.remotePass = remotePass;
  }

  ///
  /// Return a string array containing the remote directory's file list.
  ///
  ///
  ///
  public ArrayList getFileList(string mask)
  {

   if(!logined)
   {
    login();
   }

   Socket cSocket = createDataSocket();
   delay();
   //Console.Write("1/n");
   sendCommand("NLST " + mask);
   for(int i=0;i<30;i++)delay();
   //Console.Write("2/n");
   if(!(retValue == 150 || retValue == 125))
   {
    return null;
   }
   
   mes = "";

   while(true)
   {

    int bytes = cSocket.Receive(buffer, buffer.Length, 0);
    mes += ASCII.GetString(buffer, 0, bytes);

    if(bytes < buffer.Length)
    {
     break;
    }
   }

   char[] seperator = {'/n'};
   string[] mess = mes.Split(seperator);
   cSocket.Close();
   
   readReply();

   if(retValue != 226)
   {
    throw new IOException(reply.Substring(4));
   }
   ArrayList fileNames=new ArrayList();
   int size=mess.Length;
   for(int i=0;i<size-1;i++){
    fileNames.Add(mess[i].TrimEnd(new char[]{'/r'}));
   }
   return fileNames;
  }
  //get sub directory of certain directory
  public ArrayList getSubdir(string mask,ref ArrayList  fileNames)
  {

   if(!logined)
   {
    login();
   }

   Socket cSocket = createDataSocket();
   delay();
   sendCommand("NLST -a");
   for(int i=0;i<10;i++)delay();
   if(!(retValue == 150 || retValue == 125))
   {
    throw new IOException(reply.Substring(4));
   }

   mes = "";
   
   while(true)
   {

    int bytes = cSocket.Receive(buffer, buffer.Length, 0);
    delay();
    mes += ASCII.GetString(buffer, 0, bytes);
    
    if(bytes < buffer.Length)
    {
     break;
    }
   }

   char[] seperator = {'/n'};
   string[] mess = mes.Split(seperator);

   cSocket.Close();

   readReply();

   if(retValue != 226)
   {
    throw new IOException(reply.Substring(4));
   }
   ArrayList subdir=new ArrayList();
   int size=mess.Length-1;
   if(fileNames==null || fileNames.Count==0)
    for(int i=2;i<size;i++){
     subdir.Add(mess[i].TrimEnd(new char[]{'/r'}));
    }
   else
   {
    for(int i=2;i<size;i++)
    {
     if(!fileNames.Contains(mess[i].TrimEnd(new char[]{'/r'})))
      subdir.Add(mess[i].TrimEnd(new char[]{'/r'}));
    }
   }
   return subdir;
  }
  ///
  /// Return the size of a file.
  ///
  ///
  ///
  public long getFileSize(string fileName)
  {

   if(!logined)
   {
    login();
   }

   sendCommand("SIZE " + fileName);
   long size=0;

   if(retValue == 213)
   {
    size = Int64.Parse(reply.Substring(4));
   }
   else
   {
    throw new IOException(reply.Substring(4));
   }

   return size;

  }
  

  ///
  /// Login to the remote server.
  ///
  public void login()
  {

   clientSocket = new
    Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
   
   IPEndPoint ep = new
    IPEndPoint(IPAddress.Parse(remoteHost), remotePort);

   try
   {
    clientSocket.Connect(ep);
    
   }
   catch(Exception)
   {
    throw new IOException("Couldn't connect to remote server");
   }
   for(int i=0;i<50;i++)delay();
   readReply();
 
   if(retValue != 220)
   {
    close();
    throw new IOException(reply.Substring(4));
   }
   if(debug)
    Console.WriteLine("USER "+remoteUser);

   sendCommand("USER "+remoteUser);

   if( !(retValue == 331 || retValue == 230) )
   {
    cleanup();
    throw new IOException(reply.Substring(4));
   }

   if( retValue != 230 )
   {
    if(debug)
     Console.WriteLine("PASS xxx");

    sendCommand("PASS "+remotePass);
    if( !(retValue == 230 || retValue == 202) )
    {
     cleanup();
     throw new IOException(reply.Substring(4));
    }
   }

   logined = true;
   Console.WriteLine("Connected to "+remoteHost);

   chdir(remotePath);

  }

  ///
  /// If the value of mode is true, set binary mode for downloads.
  /// Else, set Ascii mode.
  ///
  ///
  public void setBinaryMode(Boolean mode)
  {

   if(mode)
   {
    sendCommand("TYPE I");
   }
   else
   {
    sendCommand("TYPE A");
   }
   if (retValue != 200)
   {
    throw new IOException(reply.Substring(4));
   }
  }

  ///
  /// Download a file to the Assembly's local directory,
  /// keeping the same file name.
  ///
  ///
  public void download(string remFileName)
  {
   download(remFileName,"",false);
  }

  ///
  /// Download a remote file to the Assembly's local directory,
  /// keeping the same file name, and set the resume flag.
  ///
  ///
  ///
  public void download(string remFileName,Boolean resume)
  {
   download(remFileName,"",resume);
  }

  ///
  /// Download a remote file to a local file name which can include
  /// a path. The local file name will be created or overwritten,
  /// but the path must exist.
  ///
  ///
  ///
  public void download(string remFileName,string locFileName)
  {
   download(remFileName,locFileName,false);
  }

  ///
  /// Download a remote file to a local file name which can include
  /// a path, and set the resume flag. The local file name will be
  /// created or overwritten, but the path must exist.
  ///
  ///
  ///
  ///
  public void download(string remFileName,string
   locFileName,Boolean resume)
  {
   if(!logined)
   {
    login();
   }

   setBinaryMode(true);

   Console.WriteLine("Downloading file "+remFileName+" from "+remoteHost + "/"+remotePath);

   if (locFileName.Equals(""))
   {
    locFileName = remFileName;
   }

   if(!File.Exists(locFileName))
   {
    Stream st = File.Create(locFileName);
    st.Close();
   }

   FileStream output = new
    FileStream(locFileName,FileMode.Open);

   Socket cSocket = createDataSocket();
   delay();
   long offset = 0;

   if(resume)
   {

    offset = output.Length;

    if(offset > 0 )
    {
     sendCommand("REST "+offset);
     if(retValue != 350)
     {
      //throw new IOException(reply.Substring(4));
      //Some servers may not support resuming.
      offset = 0;
     }
    }

    if(offset > 0)
    {
     if(debug)
     {
      Console.WriteLine("seeking to " + offset);
     }
     long npos = output.Seek(offset,SeekOrigin.Begin);
     Console.WriteLine("new pos="+npos);
    }
   }

   sendCommand("RETR " + remFileName);

   if(!(retValue == 150 || retValue == 125))
   {
    throw new IOException(reply.Substring(4));
   }

   while(true)
   {

    bytes = cSocket.Receive(buffer, buffer.Length, 0);
    output.Write(buffer,0,bytes);

    if(bytes <= 0)
    {
     break;
    }
   }

   output.Close();
   if (cSocket.Connected)
   {
    cSocket.Close();
   }

   Console.WriteLine("");

   readReply();

   if( !(retValue == 226 || retValue == 250) )
   {
    throw new IOException(reply.Substring(4));
   }

  }

  ///
  /// Upload a file.
  ///
  ///
  public void upload(string fileName)
  {
   upload(fileName,false);
  }

  ///
  /// Upload a file and set the resume flag.
  ///
  ///
  ///
  public void upload(string fileName,Boolean resume)
  {

   if(!logined)
   {
    login();
   }

   Socket cSocket = createDataSocket();
   delay();
   long offset=0;

   if(resume)
   {

    try
    {

     setBinaryMode(true);
     offset = getFileSize(fileName);

    }
    catch(Exception)
    {
     offset = 0;
    }
   }

   if(offset > 0 )
   {
    sendCommand("REST " + offset);
    if(retValue != 350)
    {
     //throw new IOException(reply.Substring(4));
     //Remote server may not support resuming.
     offset = 0;
    }
   }

   sendCommand("STOR "+Path.GetFileName(fileName));

   if( !(retValue == 125 || retValue == 150) )
   {
    throw new IOException(reply.Substring(4));
   }

   // open input stream to read source file
   FileStream input = new
    FileStream(fileName,FileMode.Open);

   if(offset != 0)
   {

    if(debug)
    {
     Console.WriteLine("seeking to " + offset);
    }
    input.Seek(offset,SeekOrigin.Begin);
   }

   Console.WriteLine("Uploading file "+fileName+" to "+remotePath);

   while ((bytes = input.Read(buffer,0,buffer.Length)) > 0)
   {

    cSocket.Send(buffer, bytes, 0);

   }
   input.Close();

   Console.WriteLine("");

   if (cSocket.Connected)
   {
    cSocket.Close();
   }

   readReply();
   if( !(retValue == 226 || retValue == 250) )
   {
    throw new IOException(reply.Substring(4));
   }
  }

  ///
  /// Delete a file from the remote FTP server.
  ///
  ///
  public void deleteRemoteFile(string fileName)
  {

   if(!logined)
   {
    login();
   }

   sendCommand("DELE "+fileName);

   if(retValue != 250)
   {
    throw new IOException(reply.Substring(4));
   }

  }

  ///
  /// Rename a file on the remote FTP server.
  ///
  ///
  ///
  public void renameRemoteFile(string oldFileName,string
   newFileName)
  {

   if(!logined)
   {
    login();
   }

   sendCommand("RNFR "+oldFileName);

   if(retValue != 350)
   {
    throw new IOException(reply.Substring(4));
   }

   //  known problem
   //  rnto will not take care of existing file.
   //  i.e. It will overwrite if newFileName exist
   sendCommand("RNTO "+newFileName);
   if(retValue != 250)
   {
    throw new IOException(reply.Substring(4));
   }

  }

  ///
  /// Create a directory on the remote FTP server.
  ///
  ///
  public void mkdir(string dirName)
  {

   if(!logined)
   {
    login();
   }

   sendCommand("MKD "+dirName);

   if(retValue != 250)
   {
    throw new IOException(reply.Substring(4));
   }

  }

  ///
  /// Delete a directory on the remote FTP server.
  ///
  ///
  public void rmdir(string dirName)
  {

   if(!logined)
   {
    login();
   }

   sendCommand("RMD "+dirName);

   if(retValue != 250)
   {
    throw new IOException(reply.Substring(4));
   }

  }

  ///
  /// Change the current working directory on the remote FTP server.
  ///
  ///
  public void chdir(string dirName)
  {

   if(dirName.Equals("."))
   {
    return;
   }

   if(!logined)
   {
    login();
   }

   sendCommand("CWD "+dirName);
   
   if(retValue != 250)
   {
    Console.WriteLine("no such directory");
    throw new IOException("no such directory");
   }

   this.remotePath = dirName;

   Console.WriteLine("Current directory is "+remotePath);

  }

  ///
  /// Close the FTP connection.
  ///
  public void close()
  {

   if( clientSocket != null )
   {
    sendCommand("QUIT");
   }

   cleanup();
   Console.WriteLine("Closing...");
  }

  ///
  /// Set debug mode.
  ///
  ///
  public void setDebug(Boolean debug)
  {
   this.debug = debug;
  }

  private void readReply()
  {
   mes = "";
    
   reply = readLine();
   
   retValue = Int32.Parse(reply.Substring(0,3));
  }

  private void cleanup()
  {
   if(clientSocket!=null)
   {
    clientSocket.Close();
    clientSocket = null;
   }
   logined = false;
  }

  private string readLine()
  {

   while(true)
   {
    
    bytes = clientSocket.Receive(buffer, buffer.Length, 0); 
   
    delay();
    mes += ASCII.GetString(buffer, 0, bytes);

    if(bytes < buffer.Length)
    {
     break;
    }
    
   }

   char[] seperator = {'/n'};
   string[] mess = mes.Split(seperator);

   if(mes.Length > 2)
   {
    mes = mess[mess.Length-2];
   }
   else
   {
    mes = mess[0];
   }

   if(!mes.Substring(3,1).Equals(" "))
   {
    return readLine();
   }

   if(debug)
   {
    for(int k=0;k < mess.Length-1;k++)
    {
     Console.WriteLine(mess[k]);
    }
   }
       
   return mes;
  }

  private void sendCommand(String command)
  {
 
   Byte[] cmdBytes =
    Encoding.Default.GetBytes((command+"/r/n").ToCharArray());
   clientSocket.Send(cmdBytes, cmdBytes.Length, 0);
   
   readReply();
  }

  private Socket createDataSocket()
  {

   sendCommand("PASV");

   if(retValue != 227)
   {
    throw new IOException(reply.Substring(4));
   }

   int index1 = reply.IndexOf('(');
   int index2 = reply.IndexOf(')');
   string ipData =
    reply.Substring(index1+1,index2-index1-1);
   int[] parts = new int[6];

   int len = ipData.Length;
   int partCount = 0;
   string buf="";

   for (int i = 0; i < len && partCount <= 6; i++)
   {

    char ch = Char.Parse(ipData.Substring(i,1));
    if (Char.IsDigit(ch))
     buf+=ch;
    else if (ch != ',')
    {
     throw new IOException("Malformed PASV reply: " +
      reply);
    }

    if (ch == ',' || i+1 == len)
    {

     try
     {
      parts[partCount++] = Int32.Parse(buf);
      buf="";
     }
     catch (Exception)
     {
      throw new IOException("Malformed PASV reply: " +
       reply);
     }
    }
   }

   string ipAddress = parts[0] + "."+ parts[1]+ "." +
    parts[2] + "." + parts[3];

   int port = (parts[4] << 8) + parts[5];

   Socket s = new
    Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
   IPEndPoint ep = new
    IPEndPoint(IPAddress.Parse(ipAddress), port);

   try
   {
    s.Connect(ep);
   }
   catch(Exception)
   {
    throw new IOException("Can't connect to remote server");
   }

   return s;
  }

 }
}

ps:MS的VS 2005 中已经有专门针对FTP的Class了，有兴趣的朋友可以研究一下。