C#操作FTP服务器上的文件（包括删除文件，下载文件，上传文件等）

本文链接：https://blog.youkuaiyun.com/weixin_44634727/article/details/113338024

前言：如果未搭建FTP服务器请先搭建
文章包含了对FTP服务器的操作有以下几种（暂以前三种做说明）
删除文件
下载文件
上传文件
获取当前目录下明细(包含文件和文件夹)
获取FTP文件列表(包括文件夹)
获取当前目录下文件列表(不包括文件夹)
判断当前目录下指定的文件是否存在
创建文件夹
获取指定文件大小
更改文件名
移动文件
切换当前目录

更改情况

下面的获取指定文件夹里面的文件列表代码错误更改为如下：

        /// <summary>  
        /// 获取指定文件夹下文件列表(不包括文件夹)  
        /// </summary>  
        public string[] GetFileList(string mask, string dirName)
        {
            string[] downloadFiles = null;
            StringBuilder result = new StringBuilder();
            FtpWebRequest reqFTP;
            try
            {
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + dirName));
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                reqFTP.Method = WebRequestMethods.Ftp.ListDirectory;
                WebResponse response = reqFTP.GetResponse();
                StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);

                string line = reader.ReadLine();
                while (line != null)
                {
                    if (mask.Trim() != string.Empty && mask.Trim() != "*.*")
                    {

                        string mask_ = mask.Substring(0, mask.IndexOf("*"));
                        if (line.Substring(0, mask_.Length) == mask_)
                        {
                            result.Append(line);
                            result.Append("\n");
                        }
                    }
                    else
                    {
                        result.Append(line);
                        result.Append("\n");
                    }
                    line = reader.ReadLine();
                }
                if (result.Length == 0)
                    return new string[] { };
                result.Remove(result.ToString().LastIndexOf('\n'), 1);
                reader.Close();
                response.Close();
                downloadFiles = result.ToString().Split('\n');
            }
            catch (Exception ex)
            {
                return new string[] { };
            }

            if (downloadFiles == null)
                downloadFiles = new string[] { };
            return downloadFiles;
        }

步骤

创建winform项目
添加FTPHelper类
添加控件
添加控件的事件
实现操作

创建winform项目

在这里插入图片描述

添加FTPHelper类

解决方案中右击鼠标项目文件新建一个类
在这里插入图片描述

在这里插入图片描述

在类里面添加下面的核心代码
以下代码包含了对FTP服务器常用的操作
例如上传文件到FTP服务器从FTP服务器上下载文件删除FTP服务器上的文件等
注意需要添加的命名空间有
using System.Net;
using System.IO;
using System.Windows.Forms;
using System.Text.RegularExpressions;

  #region 字段
        string ftpURI;
        string ftpUserID;
        string ftpServerIP;
        string ftpPassword;
        string ftpRemotePath;
        #endregion

        /// <summary>  
        /// 连接FTP服务器
        /// </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 FTPHeper(string FtpServerIP, string FtpRemotePath, string FtpUserID, string FtpPassword)
        {
            ftpServerIP = FtpServerIP;
            ftpRemotePath = FtpRemotePath;
            ftpUserID = FtpUserID;
            ftpPassword = FtpPassword;
            //ftpURI = "ftp://" + ftpServerIP + "/" + ftpRemotePath + "/";
            ftpURI = "ftp://" + ftpServerIP + "/" + ftpRemotePath;
        }

        /// <summary>  
        /// 上传  filename是本地图片的地址
        /// </summary>   
        public void Upload(string filename)
        {
            FileInfo fileInf = new FileInfo(filename);
            FtpWebRequest reqFTP;
            reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + fileInf.Name));
            reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
            reqFTP.Method = WebRequestMethods.Ftp.UploadFile;
            reqFTP.KeepAlive = false;
            reqFTP.UseBinary = true;
            reqFTP.ContentLength = fileInf.Length;
            int buffLength = 2048;
            byte[] buff = new byte[buffLength];
            int contentLen;
            FileStream fs = fileInf.OpenRead();
            try
            {
                Stream strm = reqFTP.GetRequestStream();
                contentLen = fs.Read(buff, 0, buffLength);
                while (contentLen != 0)
                {
                    strm.Write(buff, 0, contentLen);
                    contentLen = fs.Read(buff, 0, buffLength);
                }
                strm.Close();
                fs.Close();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }

        /// <summary>  
        /// 下载  filePath是下载到本机的地址fileName是需要下载的文件的名字
        /// </summary>   
        public void Download(string filePath, string fileName)
        {
            try
            {
                FileStream outputStream = new FileStream(filePath + "\\" + fileName, FileMode.Create);
                FtpWebRequest reqFTP;
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + fileName));
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                reqFTP.Method = WebRequestMethods.Ftp.DownloadFile;
                reqFTP.UseBinary = true;
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream ftpStream = response.GetResponseStream();
                long cl = response.ContentLength;
                int bufferSize = 2048;
                int readCount;
                byte[] buffer = new byte[bufferSize];
                readCount = ftpStream.Read(buffer, 0, bufferSize);
                while (readCount > 0)
                {
                    outputStream.Write(buffer, 0, readCount);
                    readCount = ftpStream.Read(buffer, 0, bufferSize);
                }
                ftpStream.Close();
                outputStream.Close();
                response.Close();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }

        /// <summary>  
        /// 删除服务器的文件  fileName是需要删除的文件的名字
        /// </summary>  
        public void Delete(string fileName)
        {
            try
            {
                FtpWebRequest reqFTP;
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + fileName));
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                reqFTP.Method = WebRequestMethods.Ftp.DeleteFile;
                reqFTP.KeepAlive = false;
                string result = String.Empty;
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                long size = response.ContentLength;
                Stream datastream = response.GetResponseStream();
                StreamReader sr = new StreamReader(datastream);
                result = sr.ReadToEnd();
                sr.Close();
                datastream.Close();
                response.Close();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }

        /// <summary>  
        /// 获取当前目录下明细(包含文件和文件夹)  
        /// </summary>  
        public string[] GetFilesDetailList()
        {
            try
            {
                StringBuilder result = new StringBuilder();
                FtpWebRequest ftp;
                ftp = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI));
                ftp.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                ftp.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
                WebResponse response = ftp.GetResponse();
                StreamReader reader = new StreamReader(response.GetResponseStream());
                string line = reader.ReadLine();
                line = reader.ReadLine();
                line = reader.ReadLine();
                while (line != null)
                {
                    result.Append(line);
                    result.Append("\n");
                    line = reader.ReadLine();
                }
                result.Remove(result.ToString().LastIndexOf("\n"), 1);
                reader.Close();
                response.Close();
                return result.ToString().Split('\n');
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }

        /// <summary>  
        /// 获取FTP文件列表(包括文件夹)
        /// </summary>   
        private string[] GetAllList(string url)
        {
            List<string> list = new List<string>();
            FtpWebRequest req = (FtpWebRequest)WebRequest.Create(new Uri(url));
            req.Credentials = new NetworkCredential(ftpPassword, ftpPassword);
            req.Method = WebRequestMethods.Ftp.ListDirectory;
            req.UseBinary = true;
            req.UsePassive = true;
            try
            {
                using (FtpWebResponse res = (FtpWebResponse)req.GetResponse())
                {
                    using (StreamReader sr = new StreamReader(res.GetResponseStream()))
                    {
                        string s;
                        while ((s = sr.ReadLine()) != null)
                        {
                            list.Add(s);
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                throw (ex);
            }
            return list.ToArray();
        }

        /// <summary>  
        /// 获取当前目录下文件列表(不包括文件夹)  
        /// </summary>  
        public string[] GetFileList(string url)
        {
            StringBuilder result = new StringBuilder();
            FtpWebRequest reqFTP;
            try
            {
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(url));
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential(ftpPassword, ftpPassword);
                reqFTP.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
                WebResponse response = reqFTP.GetResponse();
                StreamReader reader = new StreamReader(response.GetResponseStream());
                string line = reader.ReadLine();
                while (line != null)
                {

                    if (line.IndexOf("<DIR>") == -1)
                    {
                        result.Append(Regex.Match(line, @"[\S]+ [\S]+", RegexOptions.IgnoreCase).Value.Split(' ')[1]);
                        result.Append("\n");
                    }
                    line = reader.ReadLine();
                }
                result.Remove(result.ToString().LastIndexOf('\n'), 1);
                reader.Close();
                response.Close();
            }
            catch (Exception ex)
            {
                throw (ex);
            }
            return result.ToString().Split('\n');
        }

        /// <summary>  
        /// 判断当前目录下指定的文件是否存在  
        /// </summary>  
        /// <param name="RemoteFileName">远程文件名</param>  
        public bool FileExist(string RemoteFileName)
        {
            string[] fileList = GetFileList("*.*");
            foreach (string str in fileList)
            {
                if (str.Trim() == RemoteFileName.Trim())
                {
                    return true;
                }
            }
            return false;
        }

        /// <summary>  
        /// 创建文件夹  
        /// </summary>   
        public void MakeDir(string dirName)
        {
            FtpWebRequest reqFTP;
            try
            {
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + dirName));
                reqFTP.Method = WebRequestMethods.Ftp.MakeDirectory;
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream ftpStream = response.GetResponseStream();
                ftpStream.Close();
                response.Close();
            }
            catch (Exception ex)
            { }
        }

        /// <summary>  
        /// 获取指定文件大小  
        /// </summary>  
        public long GetFileSize(string filename)
        {
            FtpWebRequest reqFTP;
            long fileSize = 0;
            try
            {
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + filename));
                reqFTP.Method = WebRequestMethods.Ftp.GetFileSize;
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream ftpStream = response.GetResponseStream();
                fileSize = response.ContentLength;
                ftpStream.Close();
                response.Close();
            }
            catch (Exception ex)
            { }
            return fileSize;
        }

        /// <summary>  
        /// 更改文件名  
        /// </summary> 
        public void ReName(string currentFilename, string newFilename)
        {
            FtpWebRequest reqFTP;
            try
            {
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + currentFilename));
                reqFTP.Method = WebRequestMethods.Ftp.Rename;
                reqFTP.RenameTo = newFilename;
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream ftpStream = response.GetResponseStream();
                ftpStream.Close();
                response.Close();
            }
            catch (Exception ex)
            { }
        }

        /// <summary>  
        /// 移动文件  
        /// </summary>  
        public void MovieFile(string currentFilename, string newDirectory)
        {
            ReName(currentFilename, newDirectory);
        }

        /// <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ftpURI目录下指定的文件夹  
        /// </summary>   
        public void deleteDir(string dirName)
        {
            FtpWebRequest reqFTP;
            try
            {
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + dirName));
                reqFTP.Method = WebRequestMethods.Ftp.RemoveDirectory;
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream ftpStream = response.GetResponseStream();
                ftpStream.Close();
                response.Close();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }

添加控件

添加三个按钮button1 button2 button3

在这里插入图片描述

添加控件事件

private void button1_Click(object sender, EventArgs e)
        {
        	//第二个参数为“” 意味着默认FTP的根目录 （上面新建的FTPHeper类的代码中有说明）
            FTPHeper fTPHeper = new FTPHeper("FTP服务器的IP地址", "", "FTP用户名", "FTP密码");
            //将本地路径为C:\Users\小何程序员\Desktop\截图\2021-01\devenv_Ji9KAmB1mJ.png 的图片上传到服务器根目录中
            fTPHeper.Upload(@"C:\Users\小何程序员\Desktop\截图\2021-01\devenv_Ji9KAmB1mJ.png");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            FTPHeper fTPHeper = new FTPHeper("FTP服务器的IP地址", "", "FTP用户名", "FTP密码");
            //在FTP服务器根目录中将名字为devenv_Ji9KAmB1mJ.png的图片文件下载到本地D:\develop_files\c#_windorms_for_vs_file位置中
            fTPHeper.Download(@"D:\develop_files\c#_windorms_for_vs_file", "devenv_Ji9KAmB1mJ.png");
        }

        private void button3_Click(object sender, EventArgs e)
        {
            FTPHeper fTPHeper = new FTPHeper("FTP服务器的IP地址", "", "FTP用户名", "FTP密码");
            //删除FTP服务器根目录中名字为devenv_Ji9KAmB1mJ.png的图片文件
            fTPHeper.Delete("devenv_Ji9KAmB1mJ.png");
        }