FTP上传下载 C#辅助类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.IO;
using System.Text.RegularExpressions;

public class FtpClient
{
    /// <summary>
    /// FTP请求对象
    /// </summary>
    FtpWebRequest request = null;
    /// <summary>
    /// FTP响应对象
    /// </summary>
    FtpWebResponse response = null;
    /// <summary>
    /// FTP服务器地址
    /// </summary>
    public string ftpURI { get; private set; }
    /// <summary>
    /// FTP服务器IP
    /// </summary>
    public string ftpServerIP { get; private set; }
    /// <summary>
    /// FTP服务器默认目录
    /// </summary>
    public string ftpRemotePath { get; private set; }
    /// <summary>
    /// FTP服务器登录用户名
    /// </summary>
    public string ftpUserID { get; private set; }
    /// <summary>
    /// FTP服务器登录密码
    /// </summary>
    public string ftpPassword { get; private set; }

    /// <summary>
    /// 初始化
    /// </summary>
    /// <param name="FtpServerIP">FTP连接地址</param>
    /// <param name="FtpRemotePath">指定FTP连接成功后的当前目录, 如果不指定即默认为根目录</param>
    /// <param name="FtpUserID">用户名</param>
    /// <param name="FtpPassword">密码</param>
    public FtpClient(string ftpServerIP, string ftpRemotePath, string ftpUserID, string ftpPassword)
    {
        this.ftpServerIP = ftpServerIP;
        this.ftpRemotePath = ftpRemotePath;
        this.ftpUserID = ftpUserID;
        this.ftpPassword = ftpPassword;
        this.ftpURI = "ftp://" + ftpServerIP + "/" + ftpRemotePath + "/";
    }
    ~FtpClient()
    {
        if (response != null)
        {
            response.Close();
            response = null;
        }
        if (request != null)
        {
            request.Abort();
            request = null;
        }
    }
    /// <summary>
    /// 建立FTP链接,返回响应对象
    /// </summary>
    /// <param name="uri">FTP地址</param>
    /// <param name="ftpMethod">操作命令</param>
    /// <returns></returns>
    private FtpWebResponse Open(Uri uri, string ftpMethod)
    {
        request = (FtpWebRequest)FtpWebRequest.Create(uri);
        request.Proxy = null;
        request.Method = ftpMethod;
        request.UseBinary = true;
        request.KeepAlive = false;
        request.Credentials = new NetworkCredential(this.ftpUserID, this.ftpPassword);
        return (FtpWebResponse)request.GetResponse();
    }

    /// <summary>
    /// 建立FTP链接,返回请求对象
    /// </summary>
    /// <param name="uri">FTP地址</param>
    /// <param name="ftpMethod">操作命令</param>
    private FtpWebRequest OpenRequest(Uri uri, string ftpMethod)
    {
        request = (FtpWebRequest)WebRequest.Create(urih);
        request.Proxy = null;
        request.Method = ftpMethod;
        request.UseBinary = true;
        request.KeepAlive = false;
        request.Credentials = new NetworkCredential(this.ftpUserID, this.ftpPassword);
        return request;
    }
    /// <summary>
    /// 创建目录
    /// </summary>
    /// <param name="remoteDirectoryName">目录名</param>
    public void CreateDirectory(string remoteDirectoryName)
    {
        try
        {

            response = Open(new Uri(ftpURI), WebRequestMethods.Ftp.MakeDirectory);

        }
        catch { }
    }
    /// <summary>
    /// 更改目录或文件名
    /// </summary>
    /// <param name="currentName">当前名称</param>
    /// <param name="newName">修改后新名称</param>
    public void ReName(string currentName, string newName)
    {
        request = OpenRequest(new Uri(ftpURI + currentName), WebRequestMethods.Ftp.Rename);
        request.RenameTo = newName;
        response = (FtpWebResponse)request.GetResponse();
    }
    /// <summary>
    /// 切换当前目录
    /// </summary>
    /// <param name="IsRoot">true:绝对路径 false:相对路径</param>
    public void GotoDirectory(string DirectoryName, bool IsRoot)
    {
        if (IsRoot)
            ftpRemotePath = DirectoryName;
        else
            ftpRemotePath += "/" + DirectoryName;
        ftpURI = "ftp://" + ftpServerIP + "/" + ftpRemotePath + "/";

    }
    /// <summary>
    /// 删除目录(包括下面所有子目录和子文件)
    /// </summary>
    /// <param name="remoteDirectoryName">要删除的带路径目录名：如web/test</param>
    /*
     * 例：删除test目录
     FTPHelper helper = new FTPHelper("x.x.x.x", "web", "user", "password");
     helper.RemoveDirectory("web/test");
     */
    public void RemoveDirectory(string remoteDirectoryName)
    {
        GotoDirectory(remoteDirectoryName, true);
        var listAll = ListFilesAndDirectories();
        foreach (var m in listAll)
        {
            if (m.IsDirectory)
                RemoveDirectory(m.Path);
            else
                DeleteFile(m.Name);
        }
        GotoDirectory(remoteDirectoryName, true);
        response = Open(new Uri(ftpURI), WebRequestMethods.Ftp.RemoveDirectory);
    }
    /// <summary>
    /// 文件上传
    /// </summary>
    /// <param name="localFilePath">本地文件路径</param>
    public bool Upload(string localFilePath,ref string Errmsg)
    {
        try
        {
            FileInfo fileInf = new FileInfo(localFilePath);

            request = OpenRequest(new Uri(ftpURI + fileInf.Name), WebRequestMethods.Ftp.UploadFile);
            request.ContentLength = fileInf.Length;
            int buffLength = ;
            byte[] buff = new byte[buffLength];
            int contentLen;
            using (var fs = fileInf.OpenRead())
            {
                using (var strm = request.GetRequestStream())
                {
                    contentLen = fs.Read(buff, , buffLength);
                    while (contentLen != )
                    {
                        strm.Write(buff, , contentLen);
                        contentLen = fs.Read(buff, , buffLength);
                    }
                }
            }
            return true;
        }
        catch(Exception ex)
        {
            Errmsg = ex.Message;
            return false;
        }
    }
    /// <summary>
    /// 删除文件
    /// </summary>
    /// <param name="remoteFileName">要删除的文件名</param>
    public void DeleteFile(string remoteFileName)
    {
        response = Open(new Uri(ftpURI + remoteFileName), WebRequestMethods.Ftp.DeleteFile);
    }

    /// <summary>
    /// 获取当前目录的文件和一级子目录信息
    /// </summary>
    /// <returns></returns>
    public List<FileStruct> ListFilesAndDirectories()
    {
        var fileList = new List<FileStruct>();
        response = Open(new Uri(ftpURI), WebRequestMethods.Ftp.ListDirectoryDetails);
        using (var stream = response.GetResponseStream())
        {
            using (var sr = new StreamReader(stream))
            {
                string line = null;
                while ((line = sr.ReadLine()) != null)
                {
                    if (line.Contains(".pdf"))
                    {
                        Regex reg = new Regex(@" \d{4} ");
                        var result = reg.Match(line).Groups;
                        if (result.Count > )
                        {
                            int index = line.IndexOf(result[].Value);
                            string filename = line.Substring(index + ).Trim();
                            FileStruct model = new FileStruct();
                            model.Name = filename;
                            fileList.Add(model);
                        }
                    }
                }
            }
        }
        return fileList;
    }
    /// <summary>
    /// 列出当前目录的所有文件
    /// </summary>
    public List<FileStruct> ListFiles()
    {
        var listAll = ListFilesAndDirectories();
        var listFile = listAll.Where(m => m.IsDirectory == false).ToList();
        return listFile;
    }
    /// <summary>
    /// 列出当前目录的所有一级子目录
    /// </summary>
    public List<FileStruct> ListDirectories()
    {
        var listAll = ListFilesAndDirectories();
        var listFile = listAll.Where(m => m.IsDirectory == true).ToList();
        return listFile;
    }
    /// <summary>
    /// 判断当前目录下指定的子目录或文件是否存在
    /// </summary>
    /// <param name="remoteName">指定的目录或文件名</param>
    public bool IsExist(string remoteName)
    {
        var list = ListFilesAndDirectories();
        if (list.Count(m => m.Name == remoteName) > )
            return true;
        return false;
    }
    /// <summary>
    /// 判断当前目录下指定的一级子目录是否存在
    /// </summary>
    /// <param name="RemoteDirectoryName">指定的目录名</param>
    public bool IsDirectoryExist(string remoteDirectoryName)
    {
        var listDir = ListDirectories();
        if (listDir.Count(m => m.Name == remoteDirectoryName) > )
            return true;
        return false;
    }
    /// <summary>
    /// 判断当前目录下指定的子文件是否存在
    /// </summary>
    /// <param name="RemoteFileName">远程文件名</param>
    public bool IsFileExist(string remoteFileName)
    {
        var listFile = ListFiles();
        if (listFile.Count(m => m.Name == remoteFileName) > )
            return true;
        return false;
    }

    /// <summary>
    /// 下载
    /// </summary>
    /// <param name="saveFilePath">下载后的保存路径</param>
    /// <param name="downloadFileName">要下载的文件名</param>
    public bool Download(string saveFilePath, string downloadFileName,ref string Errmsg)
    {
        Errmsg = "";
        try
        {

            string savename = saveFilePath;
            FileStream outputStream = new FileStream(savename, FileMode.Create);
            response = Open(new Uri(ftpURI + downloadFileName), WebRequestMethods.Ftp.DownloadFile);
            using (Stream ftpStream = response.GetResponseStream())
            {
                long cl = response.ContentLength;
                int bufferSize = ;
                int readCount;
                byte[] buffer = new byte[bufferSize];
                readCount = ftpStream.Read(buffer, , bufferSize);
                while (readCount > )
                {
                    outputStream.Write(buffer, , readCount);
                    readCount = ftpStream.Read(buffer, , bufferSize);
                }
            }
            outputStream.Close();
            if (File.Exists(savename))
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        catch(Exception ex) {
            LogHelpers.Info("文件下载失败："+ downloadFileName);
            InsertMsg(downloadFileName);
            Errmsg = ex.Message;
            return false;

        }
    }
    /// <summary>
    /// 插入消息到SQLITE
    /// </summary>
    /// <param name="tablename"></param>
    /// <param name="status"></param>
    /// <param name="msg"></param>
    public void InsertMsg(string downloadFileName)
    {
        string dbmsg = AppDomain.CurrentDomain.BaseDirectory + "Log\\GateWay.db";
        SqLiteDB mymsg = new SqLiteDB(dbmsg);
        string sql = "insert into downfail(Pdfname,addtime) values('"+downloadFileName+"','"+DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")+"')";
        mymsg.ExecuteSql(sql);
    }

}

public class FileStruct
{
    /// <summary>
    /// 是否为目录
    /// </summary>
    public bool IsDirectory { get; set; }
    /// <summary>
    /// 创建时间
    /// </summary>
    public DateTime CreateTime { get; set; }
    /// <summary>
    /// 文件或目录名称
    /// </summary>
    public string Name { get; set; }
    /// <summary>
    /// 路径
    /// </summary>
    public string Path { get; set; }
}
   public enum LogType
    {
        Overall,
    }
   public static class LogHelpers
   {
       public static string LogPath
       {
           get
           {
               return AppDomain.CurrentDomain.BaseDirectory + @"\log";
           }
       }

       public enum LogLevel
       {
           Info,
           Error
       }

       public static void Info(string message, LogType logType = LogType.Overall)
       {
           if (string.IsNullOrEmpty(message))
               return;
           var path = string.Format(@"\{0}\", logType.ToString());
           WriteLog(path, "", message);
       }

       public static void Error(string message, LogType logType = LogType.Overall)
       {
           if (string.IsNullOrEmpty(message))
               return;
           var path = string.Format(@"\{0}\", logType.ToString());
           WriteLog(path, "Error ", message);
       }

       public static void Error(Exception e, LogType logType = LogType.Overall)
       {
           if (e == null)
               return;
           var path = string.Format(@"\{0}\", logType.ToString());
           WriteLog(path, "Error ", e.Message);
       }

       private static void WriteLog(string path, string prefix, string message)
       {
           path = LogPath + path;
           var fileName = string.Format("{0}{1}.log", prefix, DateTime.Now.ToString("yyyyMMdd"));

           if (!Directory.Exists(path))
               Directory.CreateDirectory(path);

           using (FileStream fs = new FileStream(path + fileName, FileMode.Append, FileAccess.Write,
                                                 FileShare.Write, , FileOptions.Asynchronous))
           {
               byte[] buffer = System.Text.Encoding.UTF8.GetBytes(DateTime.Now.ToString("HH:mm:ss") + " " + message + "\r\n");
               IAsyncResult writeResult = fs.BeginWrite(buffer, , buffer.Length,
                   (asyncResult) =>
                   {
                       var fStream = (FileStream)asyncResult.AsyncState;
                       fStream.EndWrite(asyncResult);
                   },

                   fs);
               fs.Close();
           }
       }
   }

今天在下载，上传文件的时候，发现出错了，报错为：

使用 HTTP 代理时不支持请求的 FTP 命令。

后来设置

 request.Proxy = null;
解决问题。