Question

我想用FTPWebRequest构建一个小型FTP客户端，我只想帮助连接和抓取标题信息以向用户显示，我想我可以找出应用程序的其余部分。

Answer 1

很好的文章如何在.NET中构建一个简单的FTP客户端，您可以在这里找到http://aspalliance.com/1187_Building_a_Simple_FTP_Application_Using_C_20.all

我也可以给你一些建议，例如你想检查FTP服务器上是否有文件可用，在这种情况下你可以查看它的大小。

以下是负责该功能的功能：

        public bool IsFtpFileExists(string remoteUri, out long remFileSize)
        {
            FtpWebRequest request = (FtpWebRequest)WebRequest.Create(BuildServerUri(remoteUri));
            FtpWebResponse response;

            request.Method = WebRequestMethods.Ftp.GetFileSize;
            request.Credentials = new NetworkCredential(Username, Password);
            try
            {
                response = (FtpWebResponse)request.GetResponse();
                remFileSize = response.ContentLength;
                return true;
            }
            catch (WebException we)
            {
                response = we.Response as FtpWebResponse;
                if (response != null && response.StatusCode == FtpStatusCode.ActionNotTakenFileUnavailable)
                {
                    remFileSize = 0;
                    return false;
                }
                throw;
            }
        }

Answer 2

以下是获取目录信息的示例。 GetDirectoryInformation方法位于代码示例的底部。这应该涵盖基于Windows和Unix的Ftp。还有一个更完整的FTP Client code sample here。

class Ftp
    {

        public struct FileStruct
        {
            public string Flags;
            public string Owner;
            public string Group;
            public bool IsDirectory;
            public DateTime CreateTime;
            public string Name;
        }

        public enum FileListStyle
        {
            UnixStyle,
            WindowsStyle,
            Unknown
        }

        private List<FileStruct> GetList(string datastring)
        {
            List<FileStruct> myListArray = new List<FileStruct>();
            string[] dataRecords = datastring.Split('\n');
            FileListStyle _directoryListStyle = GuessFileListStyle(dataRecords);
            foreach (string s in dataRecords)
            {
                if (_directoryListStyle != FileListStyle.Unknown && s != "")
                {
                    FileStruct f = new FileStruct();
                    f.Name = "..";
                    switch (_directoryListStyle)
                    {
                        case FileListStyle.UnixStyle:
                            f = ParseFileStructFromUnixStyleRecord(s);
                            break;
                        case FileListStyle.WindowsStyle:
                            f = ParseFileStructFromWindowsStyleRecord(s);
                            break;
                    }
                    if (!(f.Name == "." || f.Name == ".."))
                    {
                        myListArray.Add(f);
                    }
                }
            }

            return myListArray; ;
        }

        private FileStruct ParseFileStructFromWindowsStyleRecord(string Record)
        {
            ///Assuming the record style as 
            /// 02-03-11  07:46PM       <DIR>          Append
            FileStruct f = new FileStruct();
            string processstr = Record.Trim();
            string dateStr = processstr.Substring(0, 8);
            processstr = (processstr.Substring(8, processstr.Length - 8)).Trim();
            string timeStr = processstr.Substring(0, 7);
            processstr = (processstr.Substring(7, processstr.Length - 7)).Trim();
            f.CreateTime = DateTime.Parse(dateStr + " " + timeStr);
            if (processstr.Substring(0, 5) == "<DIR>")
            {
                f.IsDirectory = true;
                processstr = (processstr.Substring(5, processstr.Length - 5)).Trim();
            }
            else
            {
                string[] strs = processstr.Split(new char[] { ' ' });
                processstr = strs[1].Trim();
                f.IsDirectory = false;
            }
            f.Name = processstr;  //Rest is name   
            return f;
        }


        public FileListStyle GuessFileListStyle(string[] recordList)
        {
            foreach (string s in recordList)
            {
                if (s.Length > 10 && Regex.IsMatch(s.Substring(0, 10), "(-|d)(-|r)(-|w)(-|x)(-|r)(-|w)(-|x)(-|r)(-|w)(-|x)"))
                {
                    return FileListStyle.UnixStyle;
                }

                if (s.Length > 8 && Regex.IsMatch(s.Substring(0, 8), "[0-9][0-9]-[0-9][0-9]-[0-9][0-9]"))
                {
                    return FileListStyle.WindowsStyle;
                }
            }
            return FileListStyle.Unknown;
        }

        private FileStruct ParseFileStructFromUnixStyleRecord(string record)
        {
            ///Assuming record style as
            /// dr-xr-xr-x   1 owner    group               0 Feb 25  2011 bussys
            FileStruct f = new FileStruct();
            string processstr = record.Trim();

            f.Flags = processstr.Substring(0, 9);
            f.IsDirectory = (f.Flags[0] == 'd');

            processstr = (processstr.Substring(11)).Trim();

            _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);   //skip one part

            f.Owner = _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);
            f.Group = _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);

            _cutSubstringFromStringWithTrim(ref processstr, ' ', 0);   //skip one part

            DateTime createTime = DateTime.Now;

            var dateString = _cutSubstringFromStringWithTrim(ref processstr, ' ', 8);
            DateTime.TryParse(dateString, out createTime);

            f.CreateTime = createTime;
            f.Name = processstr;   //Rest of the part is name
            return f;
        }

        private string _cutSubstringFromStringWithTrim(ref string s, char c, int startIndex)
        {
            int pos1 = s.IndexOf(c, startIndex);
            string retString = s.Substring(0, pos1);

            s = (s.Substring(pos1)).Trim();

            return retString;
        }

        public List<FileStruct> GetDirectoryInformation(string ftpUri, NetworkCredential networkCredential)
        {
            List<FileStruct> directoryInfo = new List<FileStruct>();
            try
            {
                FtpWebRequest ftpClientRequest = WebRequest.Create(ftpUri) as FtpWebRequest;
                ftpClientRequest.Method = WebRequestMethods.Ftp.ListDirectoryDetails;
                ftpClientRequest.Proxy = null;
                ftpClientRequest.Credentials = networkCredential;

                FtpWebResponse response = ftpClientRequest.GetResponse() as FtpWebResponse;
                StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.ASCII);
                string datastring = sr.ReadToEnd();
                response.Close();

                directoryInfo = GetList(datastring);

                return directoryInfo;
            }
            catch (Exception e)
            {
                return directoryInfo;
            }
        }
    }

C＃ - 连接到FTP服务器

2 个答案: