C#

前言

本篇主要记录：VS2019 WinFrm桌面应用程序实现简单的FtpClient，包含Ftp文件查看、上传和下载等功能。

准备工作

搭建WinFrm前台界面

添加必要的控件，这里主要应用到GroupBox、Label、TextBox和Button，如下图

核心代码

构造FtpHelper类

代码如下：

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

namespace FtpClientTest
{
    public class FtpHelper
    {
        // FTP连接地址
        string ftpServerIP;
        // 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
        string ftpRemotePath;
        // 用户名
        string ftpUserID;
        // 密码
        string ftpPassword;
        // 通用处理路径
        string ftpURI;

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

        /// <summary>
        /// 上传
        /// </summary>
        /// <param name="filename">本地文件全路径</param>
        public void Upload(string filename)
        {
            FileInfo fileInf = new FileInfo(filename);
            string uri = ftpURI + fileInf.Name;
            FtpWebRequest reqFTP;

            reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
            reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
            reqFTP.KeepAlive = false;
            reqFTP.Method = WebRequestMethods.Ftp.UploadFile;
            reqFTP.UseBinary = true;
            reqFTP.UsePassive = false;
            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("Ftphelper Upload Error --> " + ex.Message);
            }
        }

        /// <summary>
        /// 下载
        /// </summary>
        /// <param name="filePath">文件保存本地路径</param>
        /// <param name="fileName">Ftp上文件的路径</param>
        public void Download(string filePath, string fileName)
        {
            FtpWebRequest reqFTP;
            try
            {
                FileStream outputStream = new FileStream(filePath + "\" + fileName, FileMode.Create);

                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + fileName));
                reqFTP.Method = WebRequestMethods.Ftp.DownloadFile;
                reqFTP.UseBinary = true;
                reqFTP.UsePassive = false;
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                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("FtpHelper Download Error --> " + ex.Message);
            }
        }

        /// <summary>
        /// 删除文件
        /// </summary>
        /// <param name="fileName">Ftp上文件的名称</param>
        public void Delete(string fileName)
        {
            try
            {
                string uri = ftpURI + fileName;
                FtpWebRequest reqFTP;
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));

                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                reqFTP.KeepAlive = false;
                reqFTP.Method = WebRequestMethods.Ftp.DeleteFile;
                reqFTP.UsePassive = 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("FtpHelper Delete Error --> " + ex.Message + "  文件名:" + fileName);
            }
        }

        /// <summary>
        /// 删除文件夹
        /// </summary>
        /// <param name="folderName">Ftp上文件夹的名称</param>
        public void RemoveDirectory(string folderName)
        {
            try
            {
                string uri = ftpURI + folderName;
                FtpWebRequest reqFTP;
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));

                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                reqFTP.KeepAlive = false;
                reqFTP.Method = WebRequestMethods.Ftp.RemoveDirectory;
                reqFTP.UsePassive = 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("FtpHelper Delete Error --> " + ex.Message + "  文件名:" + folderName);
            }
        }

        /// <summary>
        /// 获取当前目录下明细(包含文件和文件夹)
        /// </summary>
        /// <returns></returns>
        public string[] GetFilesDetailList()
        {
            string[] downloadFiles;
            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;
                ftp.UsePassive = false;
                WebResponse response = ftp.GetResponse();
                StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.Default);

                //while (reader.Read() > 0)
                //{

                //}
                string line = reader.ReadLine();
                //line = reader.ReadLine();
                //line = reader.ReadLine();

                while (line != null)
                {
                    result.Append(line);
                    result.Append("
");
                    line = reader.ReadLine();
                }
                result.Remove(result.ToString().LastIndexOf("
"), 1);
                reader.Close();
                response.Close();
                return result.ToString().Split('
');
            }
            catch (Exception ex)
            {
                downloadFiles = null;
                throw new Exception("FtpHelper  Error --> " + ex.Message);
            }
        }

        /// <summary>
        /// 获取当前目录下文件列表(仅文件)
        /// </summary>
        /// <returns></returns>
        public string[] GetFileList(string mask)
        {
            string[] downloadFiles;
            StringBuilder result = new StringBuilder();
            FtpWebRequest reqFTP;
            try
            {
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI));
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                reqFTP.Method = WebRequestMethods.Ftp.ListDirectory;
                reqFTP.UsePassive = false;
                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("
");
                        }
                    }
                    else
                    {
                        result.Append(line);
                        result.Append("
");
                    }
                    line = reader.ReadLine();
                }
                result.Remove(result.ToString().LastIndexOf('
'), 1);
                reader.Close();
                response.Close();
                return result.ToString().Split('
');
            }
            catch (Exception ex)
            {
                downloadFiles = null;
                if (ex.Message.Trim() != "远程服务器返回错误: (550) 文件不可用(例如，未找到文件，无法访问文件)。")
                {
                    throw new Exception("FtpHelper GetFileList Error --> " + ex.Message.ToString());
                }
                return downloadFiles;
            }
        }

        /// <summary>
        /// 获取当前目录下所有的文件夹列表(仅文件夹)
        /// </summary>
        /// <returns></returns>
        public string[] GetDirectoryList()
        {
            string[] drectory = GetFilesDetailList();
            string m = string.Empty;
            foreach (string str in drectory)
            {
                int dirPos = str.IndexOf("<DIR>");
                if (dirPos > 0)
                {
                    /*判断 Windows 风格*/
                    m += str.Substring(dirPos + 5).Trim() + "
";
                }
                else if (str.Trim().Substring(0, 1).ToUpper() == "D")
                {
                    /*判断 Unix 风格*/
                    string dir = str.Substring(54).Trim();
                    if (dir != "." && dir != "..")
                    {
                        m += dir + "
";
                    }
                }
            }

            char[] n = new char[] { '
' };
            return m.Split(n);
        }

        /// <summary>
        /// 判断当前目录下指定的子目录是否存在
        /// </summary>
        /// <param name="RemoteDirectoryName">指定的目录名</param>
        public bool DirectoryExist(string RemoteDirectoryName)
        {
            string[] dirList = GetDirectoryList();
            foreach (string str in dirList)
            {
                if (str.Trim() == RemoteDirectoryName.Trim())
                {
                    return true;
                }
            }
            return false;
        }

        /// <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>
        /// <param name="dirName"></param>
        public void MakeDir(string dirName)
        {
            FtpWebRequest reqFTP;
            try
            {
                // dirName = name of the directory to create.
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(ftpURI + dirName));
                reqFTP.Method = WebRequestMethods.Ftp.MakeDirectory;
                reqFTP.UseBinary = true;
                reqFTP.UsePassive = false;
                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("FtpHelper MakeDir Error --> " + ex.Message);
            }
        }

        /// <summary>
        /// 获取指定文件大小
        /// </summary>
        /// <param name="filename"></param>
        /// <returns></returns>
        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.UsePassive = false;
                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)
            {
                throw new Exception("FtpHelper GetFileSize Error --> " + ex.Message);
            }
            return fileSize;
        }

        /// <summary>
        /// 改名
        /// </summary>
        /// <param name="currentFilename"></param>
        /// <param name="newFilename"></param>
        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.UsePassive = false;
                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("FtpHelper ReName Error --> " + ex.Message);
            }
        }

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

        /// <summary>
        /// 切换当前目录
        /// </summary>
        /// <param name="DirectoryName"></param>
        /// <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>
        /// 删除订单目录
        /// </summary>
        /// <param name="ftpServerIP">FTP 主机地址</param>
        /// <param name="folderToDelete">FTP 用户名</param>
        /// <param name="ftpUserID">FTP 用户名</param>
        /// <param name="ftpPassword">FTP 密码</param>
        public static void DeleteOrderDirectory(string ftpServerIP, string folderToDelete, string ftpUserID, string ftpPassword)
        {
            try
            {
                if (!string.IsNullOrEmpty(ftpServerIP) && !string.IsNullOrEmpty(folderToDelete) && !string.IsNullOrEmpty(ftpUserID) && !string.IsNullOrEmpty(ftpPassword))
                {
                    FtpHelper fw = new FtpHelper(ftpServerIP, folderToDelete, ftpUserID, ftpPassword);
                    //进入订单目录
                    fw.GotoDirectory(folderToDelete, true);
                    //获取规格目录
                    string[] folders = fw.GetDirectoryList();
                    foreach (string folder in folders)
                    {
                        if (!string.IsNullOrEmpty(folder) || folder != "")
                        {
                            //进入订单目录
                            string subFolder = folderToDelete + "/" + folder;
                            fw.GotoDirectory(subFolder, true);
                            //获取文件列表
                            string[] files = fw.GetFileList("*.*");
                            if (files != null)
                            {
                                //删除文件
                                foreach (string file in files)
                                {
                                    fw.Delete(file);
                                }
                            }
                            //删除冲印规格文件夹
                            fw.GotoDirectory(folderToDelete, true);
                            fw.RemoveDirectory(folder);
                        }
                    }

                    //删除订单文件夹
                    string parentFolder = folderToDelete.Remove(folderToDelete.LastIndexOf('/'));
                    string orderFolder = folderToDelete.Substring(folderToDelete.LastIndexOf('/') + 1);
                    fw.GotoDirectory(parentFolder, true);
                    fw.RemoveDirectory(orderFolder);
                }
                else
                {
                    throw new Exception("FTP 及路径不能为空！");
                }
            }
            catch (Exception ex)
            {
                throw new Exception("删除订单时发生错误，错误信息为：" + ex.Message);
            }
        }
    }
}

配合控件重写Ftp方法

代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace FtpClientTest
{
    public partial class FrmMain : Form
    {
        public FrmMain()
        {
            InitializeComponent();
        }

        // 定义全局变量 ftp参数
        private FtpHelper ftpHelper;
        private string ipAddr;
        private string port;
        private string path;
        private string userName;
        private string password;

        /// <summary>
        /// 方法：Ftp初始化
        /// </summary>
        private void FtpInit()
        {
            ipAddr = this.txtHost.Text;
            port = this.txtHost.Text;
            path = this.txtCurrentDir.Text;
            userName = this.txtUserName.Text;
            password = this.txtPassCode.Text;
            ftpHelper = new FtpHelper(ipAddr, path, userName, password);
        }
 
        /// <summary>
        /// 事件：文件下载
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnDownLoad_Click(object sender, EventArgs e)
        {
            try
            {
                ftpHelper.Download(@"D:", this.txtFilePath.Text.Trim());
                MessageBox.Show("下载成功！", "提示");
            }
            catch (Exception ex)
            {
                MessageBox.Show("下载失败！错误信息[" + ex.Message + "]", "警告");
            }

        }
        /// <summary>
        /// 方法：获取Ftp当前目录下的文件
        /// </summary>
        private void GetFileList()
        {
            string[] str = ftpHelper.GetFilesDetailList();
            tbFileLists.Text = "";
            for (int i = 0; i < str.Length - 1; i++)
            {
                if (tbFileLists.Text.ToString() == "")
                {
                    tbFileLists.Text = str[i];
                }
                else
                {
                    tbFileLists.Text = tbFileLists.Text + "
" + str[i];
                }
            }
        }

        /// <summary>
        /// 事件：连接Ftp，获取文件列表
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnConnect_Click(object sender, EventArgs e)
        {
            try
            {
                FtpInit();
                this.btnDownLoad.Enabled = true;
                this.btnUpload.Enabled = true;
                this.btnOpen.Enabled = true;
                GetFileList();
            }
            catch (Exception ex)
            {
                this.btnDownLoad.Enabled = false;
                this.btnUpload.Enabled = false;
                this.btnOpen.Enabled = false;
                MessageBox.Show("连接失败！错误信息[" + ex.Message + "]", "警告");
            }
        }

        /// <summary>
        /// 事件：上传文件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnUpload_Click(object sender, EventArgs e)
        {
            try
            {
                ftpHelper.Upload(this.txtLocalFilePath.Text.Trim());
                MessageBox.Show("上传成功！", "提示");
            }
            catch (Exception ex)
            {
                MessageBox.Show("上传失败！错误信息[" + ex.Message + "]", "警告");
            }
        }

        /// <summary>
        /// 事件：选中需要上传的文件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void btnOpen_Click(object sender, EventArgs e)
        {
            // 创建 OpenFileDialog 对象
            OpenFileDialog ofd = new OpenFileDialog();
            // 设定默认打开文件类型,删选、设定文件显示类型
            ofd.Filter = "(*.et;*.xls;*.xlsx)|*.et;*.xls;*.xlsx|all|*.*";           
            // 显示打开文件的窗口
            ofd.ShowDialog();
            // 获得选择的文件路径，并赋值给
            this.txtLocalFilePath.Text = ofd.FileName;
        }
    }
}

实现效果

  作者：Jeremy.Wu
  出处：https://www.cnblogs.com/jeremywucnblog/
  本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。