C# - VS2019WinFrm桌面应用程序FtpClient实现

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 = ;
             byte[] buff = new byte[buffLength];
             int contentLen;
             FileStream fs = fileInf.OpenRead();
             try
             {
                 Stream strm = reqFTP.GetRequestStream();
                 contentLen = fs.Read(buff, , buffLength);
                 while (contentLen != )
                 {
                     strm.Write(buff, , contentLen);
                     contentLen = fs.Read(buff, , 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 = ;
                 int readCount;
                 byte[] buffer = new byte[bufferSize];

                 readCount = ftpStream.Read(buffer, , bufferSize);
                 while (readCount > )
                 {
                     outputStream.Write(buffer, , readCount);
                     readCount = ftpStream.Read(buffer, , 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("\n");
                     line = reader.ReadLine();
                 }
                 result.Remove(result.ToString().LastIndexOf("\n"), );
                 reader.Close();
                 response.Close();
                 return result.ToString().Split('\n');
             }
             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(, mask.IndexOf("*"));
                         if (line.Substring(, mask_.Length) == mask_)
                         {
                             result.Append(line);
                             result.Append("\n");
                         }
                     }
                     else
                     {
                         result.Append(line);
                         result.Append("\n");
                     }
                     line = reader.ReadLine();
                 }
                 result.Remove(result.ToString().LastIndexOf('\n'), );
                 reader.Close();
                 response.Close();
                 return result.ToString().Split('\n');
             }
             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 > )
                 {
                     /*判断 Windows 风格*/
                     m += str.Substring(dirPos + ).Trim() + "\n";
                 }
                 else if (str.Trim().Substring(, ).ToUpper() == "D")
                 {
                     /*判断 Unix 风格*/
                     string dir = str.Substring().Trim();
                     if (dir != "." && dir != "..")
                     {
                         m += dir + "\n";
                     }
                 }
             }

             char[] n = new char[] { '\n' };
             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 = ;
             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('/') + );
                     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 = ; i < str.Length - ; i++)
             {
                 if (tbFileLists.Text.ToString() == "")
                 {
                     tbFileLists.Text = str[i];
                 }
                 else
                 {
                     tbFileLists.Text = tbFileLists.Text + "\r\n" + 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。