C# FTP发布文件/文件夹至服务器（增删改查）

C#使用FTP发布文件或文件夹
一、选择一个已有的ftp站点，要求已知登录信息。如果没有，则本地添加ftp站点，具体添加ftp站点的教程如下，百度上有很多类似教程：

https://jingyan.baidu.com/article/dca1fa6f479469f1a4405292.html

二、选择正确的FTP操作库。可选择系统自带的FTP库，或者其他库如（推荐用FluentFTP，Nuget里可以下载到）

FluentFTP:  https://www.nuget.org/packages/FluentFTP

三、具体代码

        //用于验证登录信息是否正确
        private bool validateLogin()
        {
            try
            {
                var Ip = tbxIp.Text;
                var User = tbxUser.Text;
                var Psw = tbxPwb.Password;
                var uriStr = $"ftp://{Ip}";
                var request = FtpWebRequest.Create(new Uri(_ftpPath));
                request.Credentials = new NetworkCredential(_user, _password);
                request.Method = WebRequestMethods.Ftp.ListDirectory;
                var response = request.GetResponse();
                response.Close();
                request.Abort();
                return true;
            }
            catch (Exception ex)
            {
                //没有登录上
            }
            return false;
        }


        //获取指定服务器路径下的文件/文件夹路径，此处的path应该是ftp://xxx.xxx.xxx.xx/ABC/DEF的文件夹路径
        private List<string> GetFolders(string path)
        {
            var lstFolders = new List<string>();
            try
            {
                var ftpGetFolders = (FtpWebRequest)WebRequest.Create(new Uri(path));
                ftpGetFolders.Credentials = new NetworkCredential(_user, _password);
                ftpGetFolders.Method = WebRequestMethods.Ftp.ListDirectoryDetails;//所有的文件列表，包括文件和文件夹
                var response = ftpGetFolders.GetResponse();
                var sReader = new StreamReader(response.GetResponseStream());//获取返回的字节流并解析
                string line = sReader.ReadLine();
                while (line != null)
                {
                    if (line.Contains("<DIR>"))//所有的文件夹都有这个标志，但文件也有可能有这个命名，还是比较蛋疼的
                    {
                        string msg = line.Substring(line.LastIndexOf("<DIR>") + 5).Trim();
                        lstFolders.Add(msg);
                    }
                    line = sReader.ReadLine();
                }
                sReader.Close();
                response.Close();
                ftpGetFolders.Abort();
            }
            catch (Exception ex)
            {
                //ignore
            }
            return lstFolders;
        }


        //创建ftp文件夹，ftpFolderpath为以ftp://开头的文件夹完整路径
        private bool CreateFolder(string ftpFolderpath)
        {
            try
            {
                var ftpMakeFolder = (FtpWebRequest)WebRequest.Create(new Uri(ftpFolderpath));
                ftpMakeFolder.Credentials = new NetworkCredential(_user, _password);
                ftpMakeFolder.Method = WebRequestMethods.Ftp.MakeDirectory;
                var response = ftpMakeFolder.GetResponse();
                response.Close();
                ftpMakeFolder.Abort();
                return true;
            }
            catch (Exception)
            {//ignore
            }
            return false;

        }


        //发布文件，FilePath为本地的文件路径
        private bool PublishFile(string FilePath)
        {
            try
            {
                var newPath = @"ftp://" + Ip + Loc + $"/{Path.GetFileName(FilePath)}";//发布的具体路径，详细到文件名
                FtpWebRequest FTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(newPath));
                FTP.Method = WebRequestMethods.Ftp.UploadFile;//选择上传文件方法
                FTP.Credentials = new NetworkCredential(User, Psw);
                var fs = new FileStream(FilePath, FileMode.Open);
                int buffLength = 2048;
                byte[] buff = new byte[buffLength];
                int contentLen = 0;
                var strm = FTP.GetRequestStream();
                WaitHelper.StartWaiting();
                contentLen = fs.Read(buff, 0, buffLength);
                while (contentLen != 0)
                {
                    strm.Write(buff, 0, contentLen);
                    contentLen = fs.Read(buff, 0, buffLength);
                }
                strm.Close();
                fs.Close();
                WaitHelper.CloseWaiting();
                FTP.Abort();
                return true;
            }
            catch (Exception ex)
            {
                ControlUtility.ShowWarningMsgbox($"上传失败");
                return false;
            }
        }

本文给出的只是一个基本操作，并没有做细节上的处理。FTP类中还有许多其他的方法有待学习。