关于FTP的应用免不了要对FTP进行增删查改什么的。通过搜索，整理和修改，自己写了一个FTP的Helper类。此篇文章目的有二（2最近流行）。

• • 累积代码，方便自己以后查阅使用；
  • 分享代码，方便他人使用。

以下是类：

 以下是重点说明：

如何获取某一目录下的文件和文件夹列表。

由于FtpWebRequest类只提供了WebRequestMethods.Ftp.ListDirectory方式和WebRequestMethods.Ftp.ListDirectoryDetails方式。这个方法获取到的是包含文件列表和文件夹列表的信息。并不是单单只包含某一类。为此我们需要分析获取信息的特点。分析发现，对于文件夹会有“<DIR>”这一项，而文件没有。所以我们可以根据这个来区分。一下分别是获取文件列表和文件夹列表的代码：

获取文件夹：

/// <summary>
/// 从ftp服务器上获得文件夹列表
/// </summary>
/// <param name="RequedstPath">服务器下的相对路径</param>
/// <returns></returns>
public static List<string> GetDirctory(string RequedstPath)
{
    List<string> strs = new List<string>();
    try
    {
        string uri = path + RequedstPath;   //目标路径 path为服务器地址
        FtpWebRequest reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
        // ftp用户名和密码
        reqFTP.Credentials = new NetworkCredential(username, password);
        reqFTP.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
        WebResponse response = reqFTP.GetResponse();
        StreamReader reader = new StreamReader(response.GetResponseStream());//中文文件名

        string line = reader.ReadLine();
        while (line != null)
        {
            if (line.Contains("<DIR>"))
            {
                string msg = line.Substring(line.LastIndexOf("<DIR>")+5).Trim();
                strs.Add(msg);
            }
            line = reader.ReadLine();
        }
        reader.Close();
        response.Close();
        return strs;
    }
    catch (Exception ex)
    {
        Console.WriteLine("获取目录出错：" + ex.Message);
    }
    return strs;
}

获取文件列表

/// <summary>
/// 从ftp服务器上获得文件列表
/// </summary>
/// <param name="RequedstPath">服务器下的相对路径</param>
/// <returns></returns>
public static List<string> GetFile(string RequedstPath)
{
    List<string> strs = new List<string>();
    try
    {
        string uri = path + RequedstPath;   //目标路径 path为服务器地址
        FtpWebRequest reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
        // ftp用户名和密码
        reqFTP.Credentials = new NetworkCredential(username, password);
        reqFTP.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
        WebResponse response = reqFTP.GetResponse();
        StreamReader reader = new StreamReader(response.GetResponseStream());//中文文件名

        string line = reader.ReadLine();
        while (line != null)
        {
            if (!line.Contains("<DIR>"))
            {
                string msg = line.Substring(39).Trim();
                strs.Add(msg);
            }
            line = reader.ReadLine();
        }
        reader.Close();
        response.Close();
        return strs;
    }
    catch (Exception ex)
    {
        Console.WriteLine("获取文件出错：" + ex.Message);
    }
    return strs;
}

其他代码并不需要过多的说明，注释已经说的相当明确了。

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

namespace FtpSyn
{
    static public class FtpHelper
    {
        //基本设置
        static private string path = @"ftp://" + Helper.GetAppConfig("obj") + "/";    //目标路径
        static private string ftpip =Helper.GetAppConfig("obj");    //ftp IP地址
        static private string username = Helper.GetAppConfig("username");   //ftp用户名
        static private string password = Helper.GetAppConfig("password");   //ftp密码

        //获取ftp上面的文件和文件夹
        public static string[] GetFileList(string dir)
        {
            string[] downloadFiles;
            StringBuilder result = new StringBuilder();
            FtpWebRequest request;
            try
            {
                request = (FtpWebRequest)FtpWebRequest.Create(new Uri(path));
                request.UseBinary = true;
                request.Credentials = new NetworkCredential(username, password);//设置用户名和密码
                request.Method = WebRequestMethods.Ftp.ListDirectory;
                request.UseBinary = true;

                WebResponse response = request.GetResponse();
                StreamReader reader = new StreamReader(response.GetResponseStream());

                string line = reader.ReadLine();
                while (line != null)
                {
                    result.Append(line);
                    result.Append("\n");
                    Console.WriteLine(line);
                    line = reader.ReadLine();
                }
                // to remove the trailing '\n'
                result.Remove(result.ToString().LastIndexOf('\n'), 1);
                reader.Close();
                response.Close();
                return result.ToString().Split('\n');
            }
            catch (Exception ex)
            {
                Console.WriteLine("获取ftp上面的文件和文件夹：" + ex.Message);
                downloadFiles = null;
                return downloadFiles;
            }
        }

        /// <summary>
        /// 获取文件大小
        /// </summary>
        /// <param name="file">ip服务器下的相对路径</param>
        /// <returns>文件大小</returns>
        public static int GetFileSize(string file)
        {
            StringBuilder result = new StringBuilder();
            FtpWebRequest request;
            try
            {
                request = (FtpWebRequest)FtpWebRequest.Create(new Uri(path + file));
                request.UseBinary = true;
                request.Credentials = new NetworkCredential(username, password);//设置用户名和密码
                request.Method = WebRequestMethods.Ftp.GetFileSize;

                int dataLength = (int)request.GetResponse().ContentLength;

                return dataLength;
            }
            catch (Exception ex)
            {
                Console.WriteLine("获取文件大小出错：" + ex.Message);
                return -1;
            }
        }

        /// <summary>
        /// 文件上传
        /// </summary>
        /// <param name="filePath">原路径（绝对路径）包括文件名</param>
        /// <param name="objPath">目标文件夹：服务器下的相对路径 不填为根目录</param>
        public static void FileUpLoad(string filePath,string objPath="")
        {
            try
            {
                string url = path;
                if(objPath!="")
                    url += objPath + "/";
                try
                {

                    FtpWebRequest reqFTP = null;
                    //待上传的文件 （全路径）
                    try
                    {
                        FileInfo fileInfo = new FileInfo(filePath);
                        using (FileStream fs = fileInfo.OpenRead())
                        {
                            long length = fs.Length;
                            reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(url + fileInfo.Name));

                            //设置连接到FTP的帐号密码
                            reqFTP.Credentials = new NetworkCredential(username, password);
                            //设置请求完成后是否保持连接
                            reqFTP.KeepAlive = false;
                            //指定执行命令
                            reqFTP.Method = WebRequestMethods.Ftp.UploadFile;
                            //指定数据传输类型
                            reqFTP.UseBinary = true;

                            using (Stream stream = reqFTP.GetRequestStream())
                            {
                                //设置缓冲大小
                                int BufferLength = 5120;
                                byte[] b = new byte[BufferLength];
                                int i;
                                while ((i = fs.Read(b, 0, BufferLength)) > 0)
                                {
                                    stream.Write(b, 0, i);
                                }
                                Console.WriteLine("上传文件成功");
                            }
                        }
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine("上传文件失败错误为" + ex.Message);
                    }
                    finally
                    {

                    }
                }
                catch (Exception ex)
                {
                    Console.WriteLine("上传文件失败错误为" + ex.Message);
                }
                finally
                {

                }
            }
            catch (Exception ex)
            {
                Console.WriteLine("上传文件失败错误为" + ex.Message);
            }
        }
        
        /// <summary>
        /// 删除文件
        /// </summary>
        /// <param name="fileName">服务器下的相对路径 包括文件名</param>
        public static void DeleteFileName(string fileName)
        {
            try
            {
                FileInfo fileInf = new FileInfo(ftpip +""+ fileName);
                string uri = path + fileName;
                FtpWebRequest reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
                // 指定数据传输类型
                reqFTP.UseBinary = true;
                // ftp用户名和密码
                reqFTP.Credentials = new NetworkCredential(username, password);
                // 默认为true，连接不会被关闭
                // 在一个命令之后被执行
                reqFTP.KeepAlive = false;
                // 指定执行什么命令
                reqFTP.Method = WebRequestMethods.Ftp.DeleteFile;
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                response.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine("删除文件出错：" + ex.Message);
            }
        }
        
        /// <summary>
        /// 新建目录 上一级必须先存在
        /// </summary>
        /// <param name="dirName">服务器下的相对路径</param>
        public static void MakeDir(string dirName)
        {
            try
            {
                string uri = path + dirName;
                FtpWebRequest reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
                // 指定数据传输类型
                reqFTP.UseBinary = true;
                // ftp用户名和密码
                reqFTP.Credentials = new NetworkCredential(username, password);
                reqFTP.Method = WebRequestMethods.Ftp.MakeDirectory;
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                response.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine("创建目录出错：" + ex.Message);
            }
        }
        
        /// <summary>
        /// 删除目录 上一级必须先存在
        /// </summary>
        /// <param name="dirName">服务器下的相对路径</param>
        public static void DelDir(string dirName)
        {
            try
            {
                string uri = path + dirName;
                FtpWebRequest reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
                // ftp用户名和密码
                reqFTP.Credentials = new NetworkCredential(username, password);
                reqFTP.Method = WebRequestMethods.Ftp.RemoveDirectory;
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                response.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine("删除目录出错：" + ex.Message);
            }
        }

        /// <summary>
        /// 从ftp服务器上获得文件夹列表
        /// </summary>
        /// <param name="RequedstPath">服务器下的相对路径</param>
        /// <returns></returns>
        public static List<string> GetDirctory(string RequedstPath)
        {
            List<string> strs = new List<string>();
            try
            {
                string uri = path + RequedstPath;   //目标路径 path为服务器地址
                FtpWebRequest reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
                // ftp用户名和密码
                reqFTP.Credentials = new NetworkCredential(username, password);
                reqFTP.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
                WebResponse response = reqFTP.GetResponse();
                StreamReader reader = new StreamReader(response.GetResponseStream());//中文文件名

                string line = reader.ReadLine();
                while (line != null)
                {
                    if (line.Contains("<DIR>"))
                    {
                        string msg = line.Substring(line.LastIndexOf("<DIR>")+5).Trim();
                        strs.Add(msg);
                    }
                    line = reader.ReadLine();
                }
                reader.Close();
                response.Close();
                return strs;
            }
            catch (Exception ex)
            {
                Console.WriteLine("获取目录出错：" + ex.Message);
            }
            return strs;
        }

        /// <summary>
        /// 从ftp服务器上获得文件列表
        /// </summary>
        /// <param name="RequedstPath">服务器下的相对路径</param>
        /// <returns></returns>
        public static List<string> GetFile(string RequedstPath)
        {
            List<string> strs = new List<string>();
            try
            {
                string uri = path + RequedstPath;   //目标路径 path为服务器地址
                FtpWebRequest reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
                // ftp用户名和密码
                reqFTP.Credentials = new NetworkCredential(username, password);
                reqFTP.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
                WebResponse response = reqFTP.GetResponse();
                StreamReader reader = new StreamReader(response.GetResponseStream());//中文文件名

                string line = reader.ReadLine();
                while (line != null)
                {
                    if (!line.Contains("<DIR>"))
                    {
                        string msg = line.Substring(39).Trim();
                        strs.Add(msg);
                    }
                    line = reader.ReadLine();
                }
                reader.Close();
                response.Close();
                return strs;
            }
            catch (Exception ex)
            {
                Console.WriteLine("获取文件出错：" + ex.Message);
            }
            return strs;
        }
    
    }
}

希望对你有所帮助。