请大家帮写用socket检测FTP上目录/文件是否存在的代码
我从网上找了好些FTP的代码，测试了一下，就socket的最快。其它的代码，不知为何，在第一次连接FTP时都慢，有时长达一分钟，之后还行。 用SOCKET的就没这问题。
下面是找到的SOCKET操作FTP的源码，但是它没有检测ftp上的目录或文件是否存在的功能，而我很需要这个，能不能请大家帮写一下，谢谢。
using System;
using System.Net;
using System.IO;
using System.Text;
using System.Net.Sockets;
namespace FTP
{
/// <summary>
/// FTPClient 的摘要说明。
/// </summary>
public class FTPClient
{
#region 构造函数
/// <summary>
/// 缺省构造函数
/// </summary>
public FTPClient()
{
strRemoteHost = "";
strRemotePath = "";
strRemoteUser = "";
strRemotePass = "";
strRemotePort = 21;
bConnected = false;
} /// <summary>
/// 构造函数
/// </summary>
/// <param name="remoteHost"></param>
/// <param name="remotePath"></param>
/// <param name="remoteUser"></param>
/// <param name="remotePass"></param>
/// <param name="remotePort"></param>
public FTPClient(string remoteHost, string remotePath, string remoteUser, string remotePass, int remotePort)
{
strRemoteHost = remoteHost;
strRemotePath = remotePath;
strRemoteUser = remoteUser;
strRemotePass = remotePass;
strRemotePort = remotePort;
Connect();
}
#endregion
#region 登陆
/// <summary>
/// FTP服务器IP地址
/// </summary>
private string strRemoteHost;
public string RemoteHost
{
get
{
return strRemoteHost;
}
set
{
strRemoteHost = value;
}
}
/// <summary>
/// FTP服务器端口
/// </summary>
private int strRemotePort;
public int RemotePort
{
get
{
return strRemotePort;
}
set
{
strRemotePort = value;
}
}
/// <summary>
/// 当前服务器目录
/// </summary>
private string strRemotePath;
public string RemotePath
{
get
{
return strRemotePath;
}
set
{
strRemotePath = value;
}
}
/// <summary>
/// 登录用户账号
/// </summary>
private string strRemoteUser;
public string RemoteUser
{
set
{
strRemoteUser = value;
}
}
/// <summary>
/// 用户登录密码
/// </summary>
private string strRemotePass;
public string RemotePass
{
set
{
strRemotePass = value;
}
} /// <summary>
/// 是否登录
/// </summary>
private Boolean bConnected;
public bool Connected
{
get
{
return bConnected;
}
}
#endregion
#region 链接
/// <summary>
/// 建立连接
/// </summary>
public void Connect()
{
socketControl = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint ep = new IPEndPoint(IPAddress.Parse(RemoteHost), strRemotePort);
// 链接
try
{
socketControl.Connect(ep);
}
catch (Exception)
{
throw new IOException("Couldn't connect to remote server");
} // 获取应答码
ReadReply();
if (iReplyCode != 220)
{
DisConnect();
throw new IOException(strReply.Substring(4));
} // 登陆
SendCommand("USER " + strRemoteUser);
if (!(iReplyCode == 331 || iReplyCode == 230))
{
CloseSocketConnect();//关闭连接
throw new IOException(strReply.Substring(4));
}
if (iReplyCode != 230)
{
SendCommand("PASS " + strRemotePass);
if (!(iReplyCode == 230 || iReplyCode == 202))
{
CloseSocketConnect();//关闭连接
throw new IOException(strReply.Substring(4));
}
}
bConnected = true; // 切换到目录
ChDir(strRemotePath);
}
/// <summary>
/// 关闭连接
/// </summary>
public void DisConnect()
{
if (socketControl != null)
{
SendCommand("QUIT");
}
CloseSocketConnect();
}
#endregion
#region 传输模式 /// <summary>
/// 传输模式:二进制类型、ASCII类型
/// </summary>
public enum TransferType { Binary, ASCII }; /// <summary>
/// 设置传输模式
/// </summary>
/// <param name="ttType">传输模式</param>
public void SetTransferType(TransferType ttType)
{
if (ttType == TransferType.Binary)
{
SendCommand("TYPE I");//binary类型传输
}
else
{
SendCommand("TYPE A");//ASCII类型传输
}
if (iReplyCode != 200)
{
throw new IOException(strReply.Substring(4));
}
else
{
trType = ttType;
}
}
/// <summary>
/// 获得传输模式
/// </summary>
/// <returns>传输模式</returns>
public TransferType GetTransferType()
{
return trType;
}
#endregion
#region 文件操作
/// <summary>
/// 获得文件列表
/// </summary>
/// <param name="strMask">文件名的匹配字符串</param>
/// <returns></returns>
public string[] Dir(string strMask)
{
// 建立链接
if (!bConnected)
{
Connect();
} //建立进行数据连接的socket
Socket socketData = CreateDataSocket();
//传送命令
SendCommand("NLST " + strMask); //分析应答代码
if (!(iReplyCode == 150 || iReplyCode == 125 || iReplyCode == 226))
{
throw new IOException(strReply.Substring(4));
} //获得结果
strMsg = "";
while (true)
{
int iBytes = socketData.Receive(buffer, buffer.Length, 0);
strMsg += ASCII.GetString(buffer, 0, iBytes);
if (iBytes < buffer.Length)
{
break;
}
}
char[] seperator = { '\n' };
string[] strsFileList = strMsg.Split(seperator);
socketData.Close();//数据socket关闭时也会有返回码
if (iReplyCode != 226)
{
ReadReply();
if (iReplyCode != 226)
{
throw new IOException(strReply.Substring(4));
}
}
return strsFileList;
}
/// <summary>
/// 获取文件大小
/// </summary>
/// <param name="strFileName">文件名</param>
/// <returns>文件大小</returns>
#endregion
#region 目录操作
/// <summary>
/// 创建目录
/// </summary>
/// <param name="strDirName">目录名</param>
public void MkDir(string strDirName)
{
if (!bConnected)
{
Connect();
}
SendCommand("MKD " + strDirName);
if (iReplyCode != 257)
{
throw new IOException(strReply.Substring(4));
}
}
/// <summary>
/// 删除目录
/// </summary>
/// <param name="strDirName">目录名</param>
public void RmDir(string strDirName)
{
if (!bConnected)
{
Connect();
}
SendCommand("RMD " + strDirName);
if (iReplyCode != 250)
{
throw new IOException(strReply.Substring(4));
}
}
......................
一次贴不下全部的代码
[解决办法]
有一个WebRequestMethods.Ftp.ListDirectory;
[解决办法]
