C # Implementing FTP Uploads and downloads

C # implementing FTP download files

Beginner C # need to use FTP to download files, here to record a bit.

Using system;using system.collections.generic;using system.linq;using system.text;using System.Threading.Tasks;        Using system.net;using system.io;using System.threading;namespace ftputils{class Ftphelper {//default constant definition        private static readonly String rootpath = "/";        private static readonly int defaultreadwritetimeout = 300000;        private static readonly int defaultftpport = 21; #region Set initialization parameters private String host = String.        Empty; public string Host {get {return this.host??? string.            Empty; }} private String username = string.        Empty;            public string Username {get {return this.username; }} private String password = string.        Empty;            public string Password {get {return this.password;        }} IWebProxy proxy = null; Public IWEbproxy Proxy {get {return this.proxy;            } set {this.proxy = value;        }} private int port = Defaultftpport;            public int Port {get {return port;            } set {this.port = value;        }} private bool Enablessl = false;            public bool Enablessl {get {return enablessl;        }} private bool usepassive = true;            public bool Usepassive {get {return usepassive;            } set {this.usepassive = value;        }} private bool usebinary = true;            public bool Userbinary {get {return usebinary;         } set {       This.usebinary = value;        }} private String remotepath = RootPath;            public string RemotePath {get {return remotepath;                } set {string result = RootPath; if (!string. IsNullOrEmpty (value) && value! = rootpath) {result = Path.Combine (Path.Combine ( RootPath, value. TrimStart ('/'). TrimEnd ('/')), "/");            Stitching of the path} This.remotepath = result;        }} private int readwritetimeout = Defaultreadwritetimeout;            public int Readwritetimeout {get {return readwritetimeout;            } set {this.readwritetimeout = value;             }} #endregion #region constructor public ftphelper (string host,string Username, string password) : This (host, username, password, defaultftpport, NULL, FALSE, True, True, Defaultreadwritetimeout) {}//<summary> constructors///</summary>//<param name= "host" > Host name </param>//<param NA Me= "username" > User name </param>//<param name= "password" > Password </param>///<param name= "Por T "> Port number Default 21</param>//<param name=" proxy "> Proxy default no </param>//<param name=" enables SL "> Whether to use SSL by default </param>//<param name=" usebinary "> Use binary </param>//<param name=" Usepassive "> Gets or sets the behavior of the data transfer process for the client application </param>//<param name=" Readwritetimeout "> read/write timeout time default 5min</par Am> public Ftphelper (string host, string username, string password, int port, IWebProxy proxy, bool Enablessl, b Ool Usebinary, bool usepassive, int readwritetimeout) {this.host = host. ToLower (). StartsWith ("ftp://")? Host: "ftp://" + host;            This.username = Username;            This.password = password;            This.port = port;            This.proxy = proxy;            This.enablessl = Enablessl;            This.usebinary = usebinary;            This.usepassive = usepassive;        This.readwritetimeout = Readwritetimeout; } #endregion///<summary>///stitching URL//</summary>//<param name= "hos T "> Hostname </param>//<param name=" RemotePath "> Address </param>///<param name=" FileName "  ; file name </param>////<returns> returns the full url</returns> private string Urlcombine (string host, String RemotePath, String fileName) {string result = new Uri (the new Uri (the new Uri (host). TrimEnd ('/')), RemotePath), FileName).            ToString ();;        return result; }///<summary>//Create a connection///</summary>//<param name= "url" > Address &LT;/PARAM&G        T <Param name= "Method" > Methods </param>//<returns> return Request object </returns> private Ftpwebreques T createconnection (string URL, String method) {FtpWebRequest request = (ftpwebrequest) ftpwebrequest.cre            Ate (new Uri (URL)); Request.            Credentials = new NetworkCredential (This.username, This.password); Request.            Proxy = This.proxy; Request.            KeepAlive = false; Request.            Usebinary = usebinary; Request.            Usepassive = usepassive; Request.            Enablessl = Enablessl; Request.            Method = method;            Console.WriteLine (request);        return request; }///<summary>//Upload files///</summary>//<param name= "LocalFile" > Local Files < /param>//<param name= "remotefilename" > Upload file name </param>//<returns> upload successful return True</ret       Urns> public bool Upload (FileInfo LocalFile, string remotefilename) {     BOOL result = FALSE; if (localfile.exists) {try {string url = urlcombine (Host, Re                    Motepath, Remotefilename);                    FtpWebRequest request = createconnection (URL, WebRequestMethods.Ftp.UploadFile); using (Stream rs = Request.                        GetRequestStream ()) using (FileStream fs = Localfile.openread ()) {                        byte[] buffer = new byte[1024 * 4]; int count = fs. Read (buffer, 0, buffer.                        Length); while (Count > 0) {Rs.                            Write (buffer, 0, count); Count = fs. Read (buffer, 0, buffer.                        Length); } fs.                        Close ();                    result = true; }} catch (WebException ex) {MessageBox.Show (ex). Message);               } return result;        }//Handle local file does not exist return false; }///<summary>///download File///</summary>//<param name= "serverName" > Server file name </param>//<param name= "LocalName" > Need to save local file name </param>//<returns> download successful return TRUE&L            T;/returns> public bool Download (string serverName, String localname) {bool result = false;                using (FileStream fs = new FileStream (LocalName, FileMode.OpenOrCreate)) {try                    {String url = urlcombine (Host, RemotePath, serverName);                    Console.WriteLine (URL);                    FtpWebRequest request = createconnection (URL, WebRequestMethods.Ftp.DownloadFile); Request. Contentoffset = fs.                    Length; using (ftpwebresponse response = (ftpwebresponse) request.                    GetResponse ()){fs. Position = fs.                        Length;                        byte[] buffer = new byte[1024 * 4]; int count = Response. GetResponseStream (). Read (buffer, 0, buffer.                        Length); while (Count > 0) {fs.                            Write (buffer, 0, count); Count = Response. GetResponseStream (). Read (buffer, 0, buffer.                        Length); } response. GetResponseStream ().                    Close ();                } result = true;            } catch (WebException ex) {//Handle exceptions in FTP connection}}        return result; }    }}

Specific FtpWebRequest View documents:
Https://msdn.microsoft.com/zh-cn/library/system.net.ftpwebrequest.usepassive (v=vs.110). aspx

C # Implementing FTP Uploads and downloads