很实用的FTP操作类

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Text.RegularExpressions;
using System.Globalization;
namespace UpdateSys.Common
{
    /// <summary>
    /// ftp文件上传、下载操作类
    /// </summary>
    public class FTPHelper
    {

        /// <summary>
        /// ftp用户名，匿名为“”
        /// </summary>
        private string ftpUser;

        /// <summary>
        /// ftp用户密码，匿名为“”
        /// </summary>
        private string ftpPassWord;

        /// <summary>
        ///通过用户名，密码连接到FTP服务器
        /// </summary>
        /// <param name="ftpUser">ftp用户名，匿名为“”</param>
        /// <param name="ftpPassWord">ftp登陆密码，匿名为“”</param>
        public FTPHelper(string ftpUser, string ftpPassWord)
        {
            this.ftpUser = ftpUser;
            this.ftpPassWord = ftpPassWord;
        }

        /// <summary>
        /// 匿名访问
        /// </summary>
        public FTPHelper()
        {
            this.ftpUser = "";
            this.ftpPassWord = "";
        }

        /// <summary>
        /// 上传文件到Ftp服务器，如果ftp服务器存在名称相同的文件，会覆盖ftp原来的文件
        /// </summary>
        /// <param name="uri">把上传的文件保存为ftp服务器文件的uri,如"ftp://192.168.1.104/capture-212.avi"</param>
        /// <param name="upLoadFile">要上传的本地的文件路径，如D:\capture-2.avi</param>
        public void UpLoadFile(string UpLoadUri, string upLoadFile)
        {
            Stream requestStream = null;
            FileStream fileStream = null;
            FtpWebResponse uploadResponse = null;

            try
            {
                Uri uri = new Uri(UpLoadUri);

                FtpWebRequest uploadRequest = (FtpWebRequest)WebRequest.Create(uri);
                uploadRequest.Method = WebRequestMethods.Ftp.UploadFile;

                uploadRequest.Credentials = new NetworkCredential(ftpUser, ftpPassWord);

                requestStream = uploadRequest.GetRequestStream();
                fileStream = File.Open(upLoadFile, FileMode.Open);

                byte[] buffer = new byte[1024];
                int bytesRead;
                while (true)
                {
                    bytesRead = fileStream.Read(buffer, 0, buffer.Length);
                    if (bytesRead == 0)
                        break;
                    requestStream.Write(buffer, 0, bytesRead);
                }
                requestStream.Close();
                uploadResponse = (FtpWebResponse)uploadRequest.GetResponse();

            }
            catch (Exception ex)
            {
                throw new Exception("上传文件到ftp服务器出错，文件名：" + upLoadFile + "异常信息：" + ex.ToString());
            }
            finally
            {
                if (uploadResponse != null)
                    uploadResponse.Close();
                if (fileStream != null)
                    fileStream.Close();
                if (requestStream != null)
                    requestStream.Close();
            }
        }


        /// <summary>
        /// 上传文件到ftp服务器，如果ftp服务器上存在同名文件，文件会被覆盖
        /// 
        /// </summary>
        /// <param name="ftpDir"></param>
        /// <param name="subDir"></param>
        /// <param name="fileName"></param>
        /// <param name="upLoadFile"></param>
        public void UpLoadFile(string ftpDir,string subDir,string fileName, string upLoadFile)
        {
            Stream requestStream = null;
            FileStream fileStream = null;
            FtpWebResponse uploadResponse = null;

            try
            {
                //如果子目录不存在，新建目录
                if (!DirectoryExist(ftpDir, subDir))
                {
                    MakeDirectory(ftpDir+"/"+subDir);
                }
                Uri uri = new Uri(ftpDir+"/"+subDir+"/"+fileName);

                FtpWebRequest uploadRequest = (FtpWebRequest)WebRequest.Create(uri);
                uploadRequest.Method = WebRequestMethods.Ftp.UploadFile;

                uploadRequest.Credentials = new NetworkCredential(ftpUser, ftpPassWord);

                requestStream = uploadRequest.GetRequestStream();
                fileStream = File.Open(upLoadFile, FileMode.Open);

                byte[] buffer = new byte[1024];
                int bytesRead;
                while (true)
                {
                    bytesRead = fileStream.Read(buffer, 0, buffer.Length);
                    if (bytesRead == 0)
                        break;
                    requestStream.Write(buffer, 0, bytesRead);
                }
                requestStream.Close();
                uploadResponse = (FtpWebResponse)uploadRequest.GetResponse();

            }
            catch (Exception ex)
            {
                throw new Exception("上传文件到ftp服务器出错，文件名：" + upLoadFile + "异常信息：" + ex.ToString());
            }
            finally
            {
                if (uploadResponse != null)
                    uploadResponse.Close();
                if (fileStream != null)
                    fileStream.Close();
                if (requestStream != null)
                    requestStream.Close();
            }
        }




        /// <summary>
        /// 从ftp下载文件到本地服务器
        /// </summary>
        /// <param name="downloadUrl">要下载的ftp文件路径，如ftp://192.168.1.104/capture-2.avi</param>
        /// <param name="saveFileUrl">本地保存文件的路径，如(@"d:\capture-22.avi"</param>
        public void DownLoadFile(string downloadUrl, string saveFileUrl)
        {
            Stream responseStream = null;
            FileStream fileStream = null;
            StreamReader reader = null;

            try
            {
                // string downloadUrl = "ftp://192.168.1.104/capture-2.avi";

                FtpWebRequest downloadRequest = (FtpWebRequest)WebRequest.Create(downloadUrl);
                downloadRequest.Method = WebRequestMethods.Ftp.DownloadFile;

                //string ftpUser = "yoyo";

                //string ftpPassWord = "123456";
                downloadRequest.Credentials = new NetworkCredential(ftpUser, ftpPassWord);

                FtpWebResponse downloadResponse = (FtpWebResponse)downloadRequest.GetResponse();
                responseStream = downloadResponse.GetResponseStream();

                fileStream = File.Create(saveFileUrl);
                byte[] buffer = new byte[1024];
                int bytesRead;
                while (true)
                {
                    bytesRead = responseStream.Read(buffer, 0, buffer.Length);
                    if (bytesRead == 0)
                        break;
                    fileStream.Write(buffer, 0, bytesRead);
                }
            }
            catch (Exception ex)
            {
                throw new Exception("从ftp服务器下载文件出错，文件名：" + downloadUrl + "异常信息：" + ex.ToString());
            }
            finally
            {
                if (reader != null)
                {
                    reader.Close();
                }
                if (responseStream != null)
                {
                    responseStream.Close();
                }
                if (fileStream != null)
                {
                    fileStream.Close();
                }
            }
        }


        /// <summary>
        /// 从FTP下载文件到本地服务器,支持断点下载。实现文件夹级别的断点，而不是文件级的断点。
        /// 文件下载完成后，把本地文件的最后修改时间设置成FTP的文件最后修改时间
        /// 下次下载的时候，如果文件的最后修改时间相同，断点下载；如果最后修改时间不相同，重新下载该文件
        /// </summary>
        /// <param name="ftpUri">ftp文件路径，如"ftp://localhost/test.txt"</param>
        /// <param name="saveFile">保存文件的路径，如C:\\test.txt</param>
        public void BreakPointDownLoadFile(string ftpUri, string saveFile)
        {
            System.IO.FileStream fs = null;
            System.Net.FtpWebResponse ftpRes = null;
            System.IO.Stream resStrm = null;
            try
            {
                //下载文件的URI
                Uri u = new Uri(ftpUri);
                //设定下载文件的保存路径
                string downFile = saveFile;

                //FtpWebRequest的作成
                System.Net.FtpWebRequest ftpReq = (System.Net.FtpWebRequest)
                    System.Net.WebRequest.Create(u);
                //设定用户名和密码
                ftpReq.Credentials = new System.Net.NetworkCredential(ftpUser, ftpPassWord);
                //MethodにWebRequestMethods.Ftp.DownloadFile("RETR")设定
                ftpReq.Method = System.Net.WebRequestMethods.Ftp.DownloadFile;
                //要求终了后不关闭连接
                ftpReq.KeepAlive = true;
                //使用ASCII方式传送
                ftpReq.UseBinary = false;
                //设定PASSIVE方式无效
                ftpReq.UsePassive = false;

                //判断是否继续下载
                //继续写入下载文件的FileStream

                //if (System.IO.File.Exists(downFile))
                if (FileExistAndLastModify(ftpUri,downFile))
                {
                    //继续下载
                    ftpReq.ContentOffset = (new System.IO.FileInfo(downFile)).Length;
                    fs = new System.IO.FileStream(
                       downFile, System.IO.FileMode.Append, System.IO.FileAccess.Write);
                }
                else
                {
                    //一般下载
                    fs = new System.IO.FileStream(
                        downFile, System.IO.FileMode.Create, System.IO.FileAccess.Write);
                }

                //取得FtpWebResponse
                ftpRes = (System.Net.FtpWebResponse)ftpReq.GetResponse();
                //为了下载文件取得Stream
                resStrm = ftpRes.GetResponseStream();
                //写入下载的数据
                byte[] buffer = new byte[1024];
                while (true)
                {
                    int readSize = resStrm.Read(buffer, 0, buffer.Length);
                    if (readSize == 0)
                        break;
                    fs.Write(buffer, 0, readSize);
                }
                //下载完成，设置本地保存文件的最后修改时间=ftp文件的最后修改时间
                fs.Close();
                SetLastModifySame(ftpUri,downFile);

            }
            catch (Exception ex)
            {
                throw new Exception("从ftp服务器下载文件出错，文件名：" + ftpUri + "异常信息：" + ex.ToString());
            }
            finally
            {
                if (fs != null)
                {
                    fs.Close();
                }
                if (resStrm != null)
                {
                    resStrm.Close();
                }
                if (ftpRes != null)
                {
                    ftpRes.Close();
                }
            }
        }

        /// <summary>
        /// 判断本地文件是否存在，并且最后修改时间和ftp文件是否相同，如果文件存在，最后修改时间相同，断点下载
        /// </summary>
        /// <param name="ftpUri">FTP路径</param>
        /// <param name="saveFile">文件保存路径，绝对目录</param>
        /// <returns></returns>
        private bool FileExistAndLastModify(string ftpUri, string saveFile)
        {
            if (!File.Exists(saveFile))
            {
                return false;
            }
            FileInfo file = new FileInfo(saveFile);
            DateTime ftpFileModifyDate = GetLastModifyDate(ftpUri);
            DateTime saveFileModifyDate = file.LastWriteTime;
            if (ftpFileModifyDate != saveFileModifyDate)
            {
                return false;
            }
            return true;
        }

        /// <summary>
        /// 设置本地保存文件的最后修改时间=ftp最后修改时间
        /// </summary>
        /// <param name="ftpUri"></param>
        /// <param name="saveFile"></param>
        private void SetLastModifySame(string ftpUri,string saveFile)
        {
            FileInfo file = new FileInfo(saveFile);
            DateTime ftpFileModifyDate = GetLastModifyDate(ftpUri);
            file.LastWriteTime = ftpFileModifyDate;
        }

        #region 从FTP上下载整个文件夹，包括文件夹下的文件和文件夹

        /// <summary>
        /// 列出FTP服务器上面当前目录的所有文件和目录
        /// </summary>
        /// <param name="ftpUri">FTP目录</param>
        /// <returns></returns>
        public List<FileStruct> ListFilesAndDirectories(string ftpUri)
        {
            WebResponse webresp = null;
            StreamReader ftpFileListReader = null;
            FtpWebRequest ftpRequest = null;
            try
            {
                ftpRequest = (FtpWebRequest)WebRequest.Create(new Uri(ftpUri));
                ftpRequest.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
                ftpRequest.Credentials = new NetworkCredential(ftpUser, ftpPassWord);
                webresp = ftpRequest.GetResponse();
                ftpFileListReader = new StreamReader(webresp.GetResponseStream(), Encoding.Default);
            }
            catch (Exception ex)
            {
                throw new Exception("获取文件列表出错，错误信息如下："+ex.ToString());
            }
            string Datastring = ftpFileListReader.ReadToEnd();
            return GetList(Datastring);

        }

        /// <summary>
        /// 列出FTP目录下的所有文件
        /// </summary>
        /// <param name="ftpUri">FTP目录</param>
        /// <returns></returns>
        public List<FileStruct> ListFiles(string ftpUri)
        {
            List<FileStruct> listAll = ListFilesAndDirectories(ftpUri);
            List<FileStruct> listFile = new List<FileStruct>();
            foreach (FileStruct file in listAll)
            {
                if (!file.IsDirectory)
                {
                    listFile.Add(file);
                }
            }
            return listFile;
        }


        /// <summary>
        /// 列出FTP目录下的所有目录
        /// </summary>
        /// <param name="ftpUri">FRTP目录</param>
        /// <returns>目录列表</returns>
        public List<FileStruct> ListDirectories(string ftpUri)
        {
            List<FileStruct> listAll = ListFilesAndDirectories(ftpUri);
            List<FileStruct> listDirectory = new List<FileStruct>();
            foreach (FileStruct file in listAll)
            {
                if (file.IsDirectory)
                {
                    listDirectory.Add(file);
                }
            }
            return listDirectory;
        }

        /// <summary>
        /// 获得文件和目录列表
        /// </summary>
        /// <param name="datastring">FTP返回的列表字符信息</param>
        private List<FileStruct> GetList(string datastring)
        {
            List<FileStruct> myListArray = new List<FileStruct>();
            string[] dataRecords = datastring.Split('\n');
            FileListStyle _directoryListStyle = GuessFileListStyle(dataRecords);
            foreach (string s in dataRecords)
            {
                if (_directoryListStyle != FileListStyle.Unknown && s != "")
                {
                    FileStruct f = new FileStruct();
                    f.Name = "..";
                    switch (_directoryListStyle)
                    {
                        case FileListStyle.UnixStyle:
                            f = ParseFileStructFromUnixStyleRecord(s);
                            break;
                        case FileListStyle.WindowsStyle:
                            f = ParseFileStructFromWindowsStyleRecord(s);
                            break;
                    }
                    if (!(f.Name == "." || f.Name == ".."))
                    {
                        myListArray.Add(f);
                    }
                }
            }
            return myListArray;
        }
        /// <summary>
        /// 从Unix格式中返回文件信息
        /// </summary>
        /// <param name="Record">文件信息</param>
        private FileStruct ParseFileStructFromUnixStyleRecord(string Record)
        {
            FileStruct f = new FileStruct();
            string processstr = Record.Trim();
            f.Flags = processstr.Substring(0, 10);
            f.IsDirectory = (f.Flags[0] == 'd');
            processstr = (processstr.Substring(11)).Trim();
            _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);   //跳过一部分
            f.Owner = _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);
            f.Group = _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);

            _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);   //跳过一部分
            string yearOrTime = processstr.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries)[2];
            if (yearOrTime.IndexOf(":") >= 0)  //time
            {
                processstr = processstr.Replace(yearOrTime, DateTime.Now.Year.ToString());
            }
            f.CreateTime = DateTime.Parse(_cutSubstringFromStringWithTrim(ref processstr, ' ', 8));
            f.Name = processstr;   //最后就是名称
            return f;
        }

        /// <summary>
        /// 从Windows格式中返回文件信息
        /// </summary>
        /// <param name="Record">文件信息</param>
        private FileStruct ParseFileStructFromWindowsStyleRecord(string Record)
        {
            FileStruct f = new FileStruct();
            string processstr = Record.Trim();
            string dateStr = processstr.Substring(0, 8);
            processstr = (processstr.Substring(8, processstr.Length - 8)).Trim();
            string timeStr = processstr.Substring(0, 7);
            processstr = (processstr.Substring(7, processstr.Length - 7)).Trim();
            DateTimeFormatInfo myDTFI = new CultureInfo("en-US", false).DateTimeFormat;
            myDTFI.ShortTimePattern = "t";
            f.CreateTime = DateTime.Parse(dateStr + " " + timeStr, myDTFI);
            if (processstr.Substring(0, 5) == "<DIR>")
            {
                f.IsDirectory = true;
                processstr = (processstr.Substring(5, processstr.Length - 5)).Trim();
            }
            else
            {
                string[] strs = processstr.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);   // true);
                processstr = strs[1];
                f.IsDirectory = false;
            }
            f.Name = processstr;
            return f;
        }
        /// <summary>
        /// 按照一定的规则进行字符串截取
        /// </summary>
        /// <param name="s">截取的字符串</param>
        /// <param name="c">查找的字符</param>
        /// <param name="startIndex">查找的位置</param>
        private string _cutSubstringFromStringWithTrim(ref string s, char c, int startIndex)
        {
            int pos1 = s.IndexOf(c, startIndex);
            string retString = s.Substring(0, pos1);
            s = (s.Substring(pos1)).Trim();
            return retString;
        }
        /// <summary>
        /// 判断文件列表的方式Window方式还是Unix方式
        /// </summary>
        /// <param name="recordList">文件信息列表</param>
        private FileListStyle GuessFileListStyle(string[] recordList)
        {
            foreach (string s in recordList)
            {
                if (s.Length > 10
                 && Regex.IsMatch(s.Substring(0, 10), "(-|d)(-|r)(-|w)(-|x)(-|r)(-|w)(-|x)(-|r)(-|w)(-|x)"))
                {
                    return FileListStyle.UnixStyle;
                }
                else if (s.Length > 8
                 && Regex.IsMatch(s.Substring(0, 8), "[0-9][0-9]-[0-9][0-9]-[0-9][0-9]"))
                {
                    return FileListStyle.WindowsStyle;
                }
            }
            return FileListStyle.Unknown;
        }

        /// <summary>  
        /// 从FTP下载整个文件夹  
        /// </summary>  
        /// <param name="ftpDir">FTP文件夹路径</param>  
        /// <param name="saveDir">保存的本地文件夹路径</param>  
        public void DownFtpDir(string ftpDir, string saveDir)
        {
            List<FileStruct> files = ListFilesAndDirectories(ftpDir);
            if (!Directory.Exists(saveDir))
            {
                Directory.CreateDirectory(saveDir);
            }
            foreach (FileStruct f in files)
            {
                if (f.IsDirectory) //文件夹，递归查询
                {
                    DownFtpDir(ftpDir + "/" + f.Name, saveDir + "\\" + f.Name);
                }
                else //文件，直接下载
                {
                    BreakPointDownLoadFile(ftpDir + "/" + f.Name, saveDir + "\\" + f.Name);
                }
            }
        }

        /// <summary>
        /// 上传整个文件夹的文件到ftp 服务器
        /// </summary>
        /// <param name="localDir">本地文件夹</param>
        /// <param name="ftpDir">ftp文件夹</param>
        public void UpLoadDirToFtpServer(string localDir, string ftpDir)
        {
            if (!Directory.Exists(localDir))
            {
                throw new Exception("上传文件夹：" + localDir + "出错，因为" + localDir + "不存在！");
            }
            DirectoryInfo localDirInfo = new DirectoryInfo(localDir);
            FileInfo[] files = localDirInfo.GetFiles();
            for (int i = 0; i < files.Length; i++)
            {
                UpLoadFile(ftpDir + "/" + files[i].Name, files[i].FullName);
            }
            DirectoryInfo[] dirs = localDirInfo.GetDirectories();
            for (int j = 0; j < dirs.Length; j++)
            {
                //如果子目录不存在，新建目录
                if (!DirectoryExist(ftpDir, dirs[j].Name))
                {

                    MakeDirectory(ftpDir + "/" + dirs[j].Name);
                }
                UpLoadDirToFtpServer(dirs[j].FullName, ftpDir + "/" + dirs[j].Name);
            }

        }
        #endregion

        /// <summary>
        /// 获取ftp服务器文件的最后修改时间
        /// </summary>
        /// <param name="ftpFileUri">ftp文件的完整路径，如ftp://192.168.1.104/abcd.txt</param>
        /// <returns></returns>
        public DateTime GetLastModifyDate(string ftpFileUri)
        {
            DateTime LastModifieDate = new DateTime();
            FtpWebResponse uploadResponse = null;
            try
            {
                Uri uri = new Uri(ftpFileUri);

                FtpWebRequest uploadRequest = (FtpWebRequest)WebRequest.Create(uri);
                uploadRequest.Method = WebRequestMethods.Ftp.GetDateTimestamp;

                uploadRequest.Credentials = new NetworkCredential(ftpUser, ftpPassWord);
                uploadResponse = (FtpWebResponse)uploadRequest.GetResponse();
                LastModifieDate = uploadResponse.LastModified;
                return LastModifieDate;

            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                if (uploadResponse != null)
                    uploadResponse.Close();
            }
        }

        /// <summary>
        /// 把ftp上的文件移动到ftp的另外一个目录
        /// </summary>
        /// <param name="ftpFileUri">ftp文件路径</param>
        /// <param name="ftpDir">文件移动到的ftp目录</param>
        /// <param name="deleteFile">移动后是否删除原文件</param>
        public void MoveFileToOtherDir(string ftpFileUri, string ftpDir,bool deleteFile)
        {
 
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="ftpFileUri"></param>
        public void DeleteFile(string ftpFileUri)
        {
    
            FtpWebResponse Response = null;
            try
            {
                Uri uri = new Uri(ftpFileUri);
                FtpWebRequest Request = (FtpWebRequest)WebRequest.Create(uri);
                Request.Method = WebRequestMethods.Ftp.DeleteFile;
                Request.Credentials = new NetworkCredential(ftpUser, ftpPassWord);
               // requestStream = Request.GetRequestStream();
                Response = (FtpWebResponse)Request.GetResponse();
            }
            catch (Exception ex)
            {
                throw new Exception("从ftp删除文件出错，文件名：" + ftpFileUri + "异常信息：" + ex.ToString());
            }
            finally
            {
                if (Response != null)
                    Response.Close();
            }
        }

        /// <summary>
        /// 判断ftp指定目录下是否存在子目录
        /// </summary>
        /// <param name="ftpDir">ftp目录</param>
        /// <param name="RemoteDirectoryName">子目录名称</param>
        /// <returns></returns>
        public bool DirectoryExist(string ftpDir, string RemoteDirectoryName)
        {
            List<FileStruct> dirs = ListDirectories(ftpDir);
            foreach (FileStruct dir in dirs)
            {
                if (RemoteDirectoryName == dir.Name)
                {
                    return true;
                }
            }
            return false;
        }

        /// <summary>
        /// 判断一个远程文件是否存在服务器当前目录下面
        /// </summary>
        /// <param name="RemoteDir">远程目录</param>
        /// <param name="FileName">远程文件名称</param>
        public bool FileExist(string RemoteDir,string FileName)
        {
            List<FileStruct> files = ListFiles(RemoteDir);
            foreach (FileStruct file in files)
            {
                if (FileName == file.Name)
                {
                    return true;
                }
            }
            return false;
        }

        /// <summary>
        /// 新建目录
        /// </summary>
        /// <param name="dir"></param>
        public void MakeDirectory(string dir)
        {

            FtpWebResponse Response = null;
            try
            {
                Uri uri = new Uri(dir);
                FtpWebRequest Request = (FtpWebRequest)WebRequest.Create(uri);
                Request.Method = WebRequestMethods.Ftp.MakeDirectory;
                Request.Credentials = new NetworkCredential(ftpUser, ftpPassWord);
                // requestStream = Request.GetRequestStream();
                Response = (FtpWebResponse)Request.GetResponse();
            }
            catch (Exception ex)
            {
                throw new Exception("新建目录出错，目录：" + dir + "异常信息：" + ex.ToString());
            }
            finally
            {
                if (Response != null)
                    Response.Close();
            }
        }
    }


    #region 文件信息结构
    public struct FileStruct
    {
        public string Flags;
        public string Owner;
        public string Group;
        public bool IsDirectory;
        public DateTime CreateTime;
        public string Name;
    }
    public enum FileListStyle
    {
        UnixStyle,
        WindowsStyle,
        Unknown
    }
    #endregion

}


下载整个文件夹，调用如下：

FTPHelper FTP = new FTPHelper("userName", "passWord");
FTP.DownFtpDir("ftp://192.168.1.104/", "F:\\test");