FTP作为日常工作学习中,非常重要的一个文件传输存储空间,想必大家都非常的熟悉了,那么如何快速的实现文件的上传下载功能呢,本文以一个简单的小例子,简述如何通过FluentFTP实现文件的上传和下载功能。仅供学习分享使用,如有不足之处,还请指正。
FTP基础知识
文件传输协议(File Transfer Protocol,FTP)是用于在网络上进行文件传输的一套标准协议,它工作在 OSI 模型的第七层, TCP 模型的第四层, 即应用层, 使用 TCP 传输而不是 UDP, 客户在和服务器建立连接前要经过一个“三次握手”的过程, 保证客户与服务器之间的连接是可靠的, 而且是面向连接, 为数据传输提供可靠保证。FTP允许用户以文件操作的方式(如文件的增、删、改、查、传送等)与另一主机相互通信。然而, 用户并不真正登录到自己想要存取的计算机上面而成为完全用户, 可用FTP程序访问远程资源, 实现用户往返传输文件、目录管理以及访问电子邮件等等, 即使双方计算机可能配有不同的操作系统和文件存储方式。
FTP环境搭建
在windows操作系统中,FTP可以通过(Internet Inforamtion Services, IIS)管理器进行创建,创建成功后即可进行查看,如下所示:
FluentFTP安装
FluentFTP是一款基于.Net的FTP和FTPS的客户端动态库,操作简单便捷。
首先创建基于.Net Framework 4.6.1的winform应用程序,然后通过Nuget包管理器进行安装,如下所示:
示例演示
主要实现基于FTP的上传,下载,浏览等功能,如下所示:
进入文件夹及右键下载,如下所示:
示例源码
FtpHelper类源码,封装了FTP文件的检索,上传,下载等功能,如下所示:
using System; using System.Collections.Generic; using System.IO; using System.Linq; using System.Net; using System.Text; using System.Threading; using System.Threading.Tasks; using FluentFTP; namespace DemoFtp { public class FtpHelper { #region 属性与构造函数 /// <summary> /// IP地址 /// </summary> public string IpAddr { get; set; } /// <summary> /// 相对路径 /// </summary> public string RelatePath { get; set; } /// <summary> /// 端口号 /// </summary> public int Port { get; set; } /// <summary> /// 用户名 /// </summary> public string UserName { get; set; } /// <summary> /// 密码 /// </summary> public string Password { get; set; } public FtpHelper() { } public FtpHelper(string ipAddr, int port, string userName, string password, string relatePath) { this.IpAddr = ipAddr; this.Port = port; this.UserName = userName; this.Password = password; this.RelatePath = relatePath; } #endregion #region 方法 public FtpListItem[] ListDir() { FtpListItem[] lists; using (var ftpClient = new FtpClient(this.IpAddr, this.UserName, this.Password, this.Port)) { ftpClient.Connect(); ftpClient.SetWorkingDirectory(this.RelatePath); lists = ftpClient.GetListing(); } return lists; } public void UpLoad(string dir, string file, out bool isOk) { isOk = false; FileInfo fi = new FileInfo(file); using (FileStream fs = fi.OpenRead()) { //long length = fs.Length; using (var ftpClient = new FtpClient(this.IpAddr, this.UserName, this.Password, this.Port)) { ftpClient.Connect(); ftpClient.SetWorkingDirectory(this.RelatePath); string remotePath = dir + "/" + Path.GetFileName(file); var ftpRemodeExistsMode = file.EndsWith(".txt") ? FtpRemoteExists.Overwrite : FtpRemoteExists.Skip; FtpStatus status = ftpClient.UploadStream(fs, remotePath, ftpRemodeExistsMode, true); isOk = status == FtpStatus.Success; } } } /// <summary> /// 上传多个文件 /// </summary> /// <param name="files"></param> /// <param name="isOk"></param> public void UpLoad(string dir, string[] files, out bool isOk) { isOk = false; if (CheckDirIsExists(dir)) { foreach (var file in files) { UpLoad(dir, file, out isOk); } } } private bool CheckDirIsExists(string dir) { bool flag = false; using (var ftpClient = new FtpClient(this.IpAddr, this.UserName, this.Password, this.Port)) { ftpClient.Connect(); ftpClient.SetWorkingDirectory(this.RelatePath); flag = ftpClient.DirectoryExists(dir); if (!flag) { flag = ftpClient.CreateDirectory(dir); } } return flag; } /// <summary> /// 下载ftp /// </summary> /// <param name="localAddress"></param> /// <param name="remoteAddress"></param> /// <returns></returns> public bool DownloadFile(string localAddress, string remoteAddress) { using (var ftpClient = new FtpClient(this.IpAddr, this.UserName, this.Password, this.Port)) { ftpClient.SetWorkingDirectory("/"); ftpClient.Connect(); if (ftpClient.DownloadFile(localAddress, remoteAddress) == FtpStatus.Success) { return true; } return false; } } #endregion } }
每一个FTP文件或文件夹,由一个自定义用户控件【PictureBox+Label+ContextMenu】表示,这样便于处理与显示:
using DemoFtp.Properties; using FluentFTP; using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.IO; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace DemoFtp { public partial class FtpElementControl : UserControl { public Action<FtpListItem> SubFolderClick; public Action<FtpListItem> DownLoadClick; private FtpListItem ftpListItem; public FtpElementControl(FtpListItem ftpListItem) { InitializeComponent(); this.ftpListItem = ftpListItem; } public FtpElementControl() { InitializeComponent(); } public void InitControl() { if (ftpListItem.Type == FtpObjectType.Directory) { this.pbIcon.Image = Resources.folder.ToBitmap(); } else if (ftpListItem.Type == FtpObjectType.File) { var name = ftpListItem.Name; var ext = Path.GetExtension(name).ToLower().Substring(1); if (ext == "png" || ext == "jpeg" || ext == "jpg" || ext == "bmp" || ext == "gif") { this.pbIcon.Image = Resources.pictures.ToBitmap(); } else if (ext == "doc" || ext == "docx") { this.pbIcon.Image = Resources.doc.ToBitmap(); } else if (ext == "exe") { this.pbIcon.Image = Resources.setup.ToBitmap(); } else { this.pbIcon.Image = Resources.file; } } else { this.pbIcon.Image = Resources.file; } this.lblName.Text = ftpListItem.Name; } private void FtpElementControl_Load(object sender, EventArgs e) { } /// <summary> /// 子菜单下载功能 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void menu_ItemClicked(object sender, ToolStripItemClickedEventArgs e) { this.DownLoadClick?.Invoke(ftpListItem); } /// <summary> /// 双击打开 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void pbIcon_DoubleClick(object sender, EventArgs e) { this.SubFolderClick?.Invoke(ftpListItem); } } }
主页面由一系列用户操作框和按钮组成,完成对FTP的基本操作,如下所示:
using FluentFTP; using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.IO; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace DemoFtp { public partial class MainForm : Form { private FtpHelper ftpHelper; public MainForm() { InitializeComponent(); } private void btnLogin_Click(object sender, EventArgs e) { var url = txtFtpUrl.Text; var userName = txtUserName.Text; var password = txtPassword.Text; var port = txtPort.Text; if (this.lblRelatePath.Text != "/") { this.lblRelatePath.Text = "/"; } var relatePath = this.lblRelatePath.Text; if (string.IsNullOrEmpty(url) || string.IsNullOrEmpty(userName) || string.IsNullOrEmpty(password) || string.IsNullOrEmpty(port)) { MessageBox.Show("路径和账号密码不可为空"); return; } if (ftpHelper == null) { ftpHelper = new FtpHelper(url, int.Parse(port), userName, password, relatePath); } ListDir(); } public void SubFolder(FtpListItem ftpListItem) { if (ftpListItem.Type == FtpObjectType.Directory) { var fullName = ftpListItem.FullName; ftpHelper.RelatePath = fullName; ListDir(); this.lblRelatePath.Text = fullName; } } private void Download(FtpListItem ftpListItem) { var fullName=ftpListItem.FullName; var fileName = Path.GetFileName(fullName); SaveFileDialog sfd = new SaveFileDialog(); sfd.FileName = fileName; sfd.Title = "不载"; sfd.Filter = "所有文档|*.*"; if (DialogResult.OK == sfd.ShowDialog()) { ftpHelper.DownloadFile(sfd.FileName, fullName); } } private void ListDir() { this.ftpContainer.Controls.Clear(); var ftpListItems = this.ftpHelper.ListDir(); if (ftpListItems != null && ftpListItems.Length > 0) { foreach (var ftpListItem in ftpListItems) { FtpElementControl ftpControl = new FtpElementControl(ftpListItem); ftpControl.InitControl(); ftpControl.DownLoadClick += Download; ftpControl.SubFolderClick += SubFolder; this.ftpContainer.Controls.Add(ftpControl); } } } private void btnUpload_Click(object sender, EventArgs e) { OpenFileDialog ofd = new OpenFileDialog(); ofd.Filter = "所有文件|*.*"; ofd.Title = "请选择需要上传的文件"; if (DialogResult.OK == ofd.ShowDialog()) { var localFile=ofd.FileName; ftpHelper.UpLoad(this.lblRelatePath.Text, localFile, out bool isOk); if (isOk) { ListDir(); } } } private void pbReturn_Click(object sender, EventArgs e) { var relativePath=this.lblRelatePath.Text; if (relativePath == "/") { return; } relativePath = relativePath.Substring(0, relativePath.LastIndexOf("/")+1); ftpHelper.RelatePath=relativePath; ListDir(); this.lblRelatePath.Text = relativePath; } } }
以上就是基于FluentFTP实现FTP上传下载的全部内容,旨在抛砖引玉,共同学习,一起进步。