平时根本没时间搞FTP什么的，现在这个项目需要搞FTP，为什么呢，我给大家说下项目背景，我们的一个应用程序上需要上传图片，但是用户部署程序的服务器上不让上传任何东西，给了我们一个FTP账号和密码，让我们把图片保存到另一台所谓的文件服务器上面。
建立ftp通信，写入文件流，ok ， 但是显示的时候就麻烦了，不能直接写<img src = "ftp://121.131.131.1" />这样的代码啊，因为这样写的话，你浏览的时候还要登陆Ftp账户，每次都要弹出一个用户登陆框，So，决定显示图片的时候再把图片读出来放到内存里，然后输出到Response里面，把Response的ContentType设置成相对应的类型，比如 Image/gif Image/jpeg Image/png Appliaction/pdf.
下面是一些常用的ftp操作文件的方法（摘抄于网络） 不过获取文件 和获取文件夹和文件 有问题，本人已重写过
using System; using System.Collections.Generic; using System.Text; using System.IO; using System.Net; using System.Windows.Forms; using System.Globalization; namespace FtpTest1 { public class FtpWeb { string ftpServerIP; string ftpRemotePath; string ftpUserID; string ftpPassword; 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 FtpWeb(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"></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.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) { Insert_Standard_ErrorLog.Insert("FtpWeb", "Upload Error --> " + ex.Message); } } /// <summary> /// 下载 /// </summary> /// <param name="filePath"></param> /// <param name="fileName"></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.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) { Insert_Standard_ErrorLog.Insert("FtpWeb", "Download Error --> " + ex.Message); } } /// <summary> /// 删除文件 /// </summary> /// <param name="fileName"></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; 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) { Insert_Standard_ErrorLog.Insert("FtpWeb", "Delete Error --> " + ex.Message + " 文件名:" + fileName); } } /// <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; 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) { downloadFiles = null; Insert_Standard_ErrorLog.Insert("FtpWeb", "GetFilesDetailList Error --> " + ex.Message); return downloadFiles; } } /// <summary> /// 获取FTP文件列表包括文件夹 /// </summary> /// <returns></returns> private string[] GetAllList(string url,string userid,string password) { List<string> list = new List<string>(); FtpWebRequest req = (FtpWebRequest)WebRequest.Create(new Uri(url)); req.Credentials = new NetworkCredential(userid, password); 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> /// <returns></returns> public string[] GetFileList(string url,string userid,string password) { StringBuilder result = new StringBuilder(); FtpWebRequest reqFTP; try { reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(url)); reqFTP.UseBinary = true; reqFTP.Credentials = new NetworkCredential(userid, password); 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.Credentials = new NetworkCredential(ftpUserID, ftpPassword); FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse(); Stream ftpStream = response.GetResponseStream(); ftpStream.Close(); response.Close(); } catch (Exception ex) { Insert_Standard_ErrorLog.Insert("FtpWeb", "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.Credentials = new NetworkCredential(ftpUserID, ftpPassword); FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse(); Stream ftpStream = response.GetResponseStream(); fileSize = response.ContentLength; ftpStream.Close(); response.Close(); } catch (Exception ex) { Insert_Standard_ErrorLog.Insert("FtpWeb", "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.Credentials = new NetworkCredential(ftpUserID, ftpPassword); FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse(); Stream ftpStream = response.GetResponseStream(); ftpStream.Close(); response.Close(); } catch (Exception ex) { Insert_Standard_ErrorLog.Insert("FtpWeb", "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 + "/"; } }