Unable to write data to the transport connection: An established connection

DotNet68
Hello,



I'm trying to upload a file programatically and occasionally I get the

following error message.



Unable to write data to the transport connection: An established connection

was aborted by the software in your host machine.



Stack Trace

at System.Net.Sockets.NetworkStream.Write(Byte[] buffer, Int32 offset, Int32

size)

at System.Net.FtpDataStream.Write(Byte[] buffer, Int32 offset, Int32

size)

at HSMoveFiles.FTPClient.Upload(FileInfo fi, String targetFilename) in

C:\DOTNET\HSMoveFiles\FTPClient.cs:line 177



The source code for FTPClient.cs came from the following URL

www.codeproject.com/vb/net/FtpClient.asp



The exception is been thrown when trying to write the Stream.

rs.Write(content, 0, dataRead)



Has anyone got any Idea why this might happen and how to solve it?



Exception is caught at line number 185. Throw ex;.



Here is the source code. See line number 177.



using System.Collections.Generic;



using System;



using System.Net;



using System.IO;



using System.Runtime.Remoting.Lifetime;



using System.Text.RegularExpressions;



namespace HSMoveFiles



{



#region "FTP client class"



/// <summary>



/// A wrapper class for .NET 2.0 FTP



/// </summary>



/// <remarks>



/// This class does not hold open an FTP connection but



/// instead is stateless: for each FTP request it



/// connects, performs the request and disconnects.



/// </remarks>



public class FTPClient



{







#region "CONSTRUCTORS"



/// <summary>



/// Blank constructor



/// </summary>



/// <remarks>Hostname, username and password must be set manually</remarks>



public FTPClient()



{



}



/// <summary>



/// Constructor just taking the hostname



/// </summary>



/// <param name="Hostname">in either ftp.host.com or ftp.host.com

form</param>



/// <remarks></remarks>



public FTPClient(string Hostname)



{



_hostname = Hostname;



}



/// <summary>



/// Constructor taking hostname, username and password



/// </summary>



/// <param name="Hostname">in either ftp.host.com or ftp.host.com

form</param>



/// <param name="Username">Leave blank to use 'anonymous' but set password

to your email</param>



/// <param name="Password"></param>



/// <remarks></remarks>



public FTPClient(string Hostname, string Username, string Password)



{



_hostname = Hostname;



_username = Username;



_password = Password;



}



#endregion



#region "Directory functions"



/// <summary>



/// Return a simple directory listing



/// </summary>



/// <param name="directory">Directory to list, e.g. /pub</param>



/// <returns>A list of filenames and directories as a List(of

String)</returns>



/// <remarks>For a detailed directory listing, use

ListDirectoryDetail</remarks>



public List<string>ListDirectory(string directory)



{



//return a simple list of filenames in directory



System.Net.FtpWebRequest ftp = GetRequest(GetDirectory(directory));



//Set request to do simple list



ftp.Method = System.Net.WebRequestMethods.Ftp.ListDirectory;



string str = GetStringResponse(ftp);



//replace CRLF to CR, remove last instance



str = str.Replace("\r\n", "\r").TrimEnd('\r');



//split the string into a list



List<string>result = new List<string>();



result.AddRange(str.Split('\r'));



return result;



}



/// <summary>



/// Return a detailed directory listing



/// </summary>



/// <param name="directory">Directory to list, e.g. /pub/etc</param>



/// <returns>An FTPDirectory object</returns>



public FTPdirectory ListDirectoryDetail(string directory)



{



System.Net.FtpWebRequest ftp = GetRequest(GetDirectory(directory));



//Set request to do simple list



ftp.Method = System.Net.WebRequestMethods.Ftp.ListDirectoryDetails;



string str = GetStringResponse(ftp);



//replace CRLF to CR, remove last instance



str = str.Replace("\r\n", "\r").TrimEnd('\r');



//split the string into a list



return new FTPdirectory(str, _lastDirectory);



}



#endregion



#region "Upload: File transfer TO ftp server"



/// <summary>



/// Copy a local file to the FTP server



/// </summary>



/// <param name="localFilename">Full path of the local file</param>



/// <param name="targetFilename">Target filename, if required</param>



/// <returns></returns>



/// <remarks>If the target filename is blank, the source filename is used



/// (assumes current directory). Otherwise use a filename to specify a name



/// or a full path and filename if required.</remarks>



public bool Upload(string localFilename, string targetFilename)



{



//1. check source



if (!File.Exists(localFilename))



{



throw (new ApplicationException("File " + localFilename + " not found"));



}



//copy to FI



FileInfo fi = new FileInfo(localFilename);



return Upload(fi, targetFilename);



}



/// <summary>



/// Upload a local file to the FTP server



/// </summary>



/// <param name="fi">Source file</param>



/// <param name="targetFilename">Target filename (optional)</param>



/// <returns></returns>



public bool Upload(FileInfo fi, string targetFilename)



{



//copy the file specified to target file: target file can be full path or

just filename (uses current dir)



//1. check target



string target;



if (targetFilename.Trim() == "")



{



//Blank target: use source filename & current dir



target = this.CurrentDirectory + fi.Name;



}



else if (targetFilename.Contains("/"))



{



//If contains / treat as a full path



target = AdjustDir(targetFilename);



}



else



{



//otherwise treat as filename only, use current directory



target = CurrentDirectory + targetFilename;



}



string URI = Hostname + target;



//perform copy



System.Net.FtpWebRequest ftp = GetRequest(URI);



//Set request to upload a file in binary



ftp.Method = System.Net.WebRequestMethods.Ftp.UploadFile;



ftp.UseBinary = true;



//Notify FTP of the expected size



ftp.ContentLength = fi.Length;



//create byte array to store: ensure at least 1 byte!



int BufferSize = 2048;



byte[] content = new byte[BufferSize - 1 + 1];



int dataRead;



//open file for reading



using (FileStream fs = fi.OpenRead())



{



try



{



//open request to send



using (Stream rs = ftp.GetRequestStream())



{



do



{



dataRead = fs.Read(content, 0, BufferSize);



rs.Write(content, 0, dataRead);



} while (!(dataRead < BufferSize));



rs.Close();



}



}



catch (Exception ex)



{



throw ex;



}



finally



{



//ensure file closed



fs.Close();



ftp = null;



}



}



return true;



}



#endregion



#region "Download: File transfer FROM ftp server"



/// <summary>



/// Copy a file from FTP server to local



/// </summary>



/// <param name="sourceFilename">Target filename, if required</param>



/// <param name="localFilename">Full path of the local file</param>



/// <returns></returns>



/// <remarks>Target can be blank (use same filename), or just a filename



/// (assumes current directory) or a full path and filename</remarks>



public bool Download(string sourceFilename, string localFilename, bool

PermitOverwrite)



{



//2. determine target file



FileInfo fi = new FileInfo(localFilename);



return this.Download(sourceFilename, fi, PermitOverwrite);



}



//Version taking an FtpFileInfo



public bool Download(FTPfileInfo file, string localFilename, bool

PermitOverwrite)



{



return this.Download(file.FullName, localFilename, PermitOverwrite);



}



//Another version taking FtpFileInfo and FileInfo



public bool Download(FTPfileInfo file, FileInfo localFI, bool

PermitOverwrite)



{



return this.Download(file.FullName, localFI, PermitOverwrite);



}



//Version taking string/FileInfo



public bool Download(string sourceFilename, FileInfo targetFI, bool

PermitOverwrite)



{



//1. check target



if (targetFI.Exists && !(PermitOverwrite))



{



throw (new ApplicationException("Target file already exists"));



}



//2. check source



string target;



if (sourceFilename.Trim() == "")



{



throw (new ApplicationException("File not specified"));



}



else if (sourceFilename.Contains("/"))



{



//treat as a full path



target = AdjustDir(sourceFilename);



}



else



{



//treat as filename only, use current directory



target = CurrentDirectory + sourceFilename;



}



string URI = Hostname + target;



//3. perform copy



System.Net.FtpWebRequest ftp = GetRequest(URI);



//Set request to download a file in binary mode



ftp.Method = System.Net.WebRequestMethods.Ftp.DownloadFile;



ftp.UseBinary = true;



//open request and get response stream



using (FtpWebResponse response = (FtpWebResponse)ftp.GetResponse())



{



using (Stream responseStream = response.GetResponseStream())



{



//loop to read & write to file



using (FileStream fs = targetFI.OpenWrite())



{



try



{



byte[] buffer = new byte[2048];



int read = 0;



do



{



read = responseStream.Read(buffer, 0, buffer.Length);



fs.Write(buffer, 0, read);



} while (!(read == 0));



responseStream.Close();



fs.Flush();



fs.Close();



}



catch (Exception)



{



//catch error and delete file only partially downloaded



fs.Close();



//delete target file as it's incomplete



targetFI.Delete();



throw;



}



}



responseStream.Close();



}



response.Close();



}







return true;



}



#endregion



#region "Other functions: Delete rename etc."



/// <summary>



/// Delete remote file



/// </summary>



/// <param name="filename">filename or full path</param>



/// <returns></returns>



/// <remarks></remarks>



public bool FtpDelete(string filename)



{



//Determine if file or full path



string URI = this.Hostname + GetFullPath(filename);



System.Net.FtpWebRequest ftp = GetRequest(URI);



//Set request to delete



ftp.Method = System.Net.WebRequestMethods.Ftp.DeleteFile;



try



{



//get response but ignore it



string str = GetStringResponse(ftp);



}



catch (Exception)



{



return false;



}



return true;



}



/// <summary>



/// Determine if file exists on remote FTP site



/// </summary>



/// <param name="filename">Filename (for current dir) or full path</param>



/// <returns></returns>



/// <remarks>Note this only works for files</remarks>



public bool FtpFileExists(string filename)



{



//Try to obtain filesize: if we get error msg containing "550"



//the file does not exist



try



{



long size = GetFileSize(filename);



return true;



}



catch (Exception ex)



{



//only handle expected not-found exception



if (ex is System.Net.WebException)



{



//file does not exist/no rights error = 550



if (ex.Message.Contains("550"))



{



//clear



return false;



}



else



{



throw;



}



}



else



{



throw;



}



}



}



/// <summary>



/// Determine size of remote file



/// </summary>



/// <param name="filename"></param>



/// <returns></returns>



/// <remarks>Throws an exception if file does not exist</remarks>



public long GetFileSize(string filename)



{



string path;



if (filename.Contains("/"))



{



path = AdjustDir(filename);



}



else



{



path = this.CurrentDirectory + filename;



}



string URI = this.Hostname + path;



System.Net.FtpWebRequest ftp = GetRequest(URI);



//Try to get info on file/dir?



ftp.Method = System.Net.WebRequestMethods.Ftp.GetFileSize;



string tmp = this.GetStringResponse(ftp);



return GetSize(ftp);



}



public bool FtpRename(string sourceFilename, string newName)



{



//Does file exist?



string source = GetFullPath(sourceFilename);



if (!FtpFileExists(source))



{



throw (new FileNotFoundException("File " + source + " not found"));



}



//build target name, ensure it does not exist



string target = GetFullPath(newName);



if (target == source)



{



throw (new ApplicationException("Source and target are the same"));



}



else if (FtpFileExists(target))



{



throw (new ApplicationException("Target file " + target + " already

exists"));



}



//perform rename



string URI = this.Hostname + source;



System.Net.FtpWebRequest ftp = GetRequest(URI);



//Set request to delete



ftp.Method = System.Net.WebRequestMethods.Ftp.Rename;



ftp.RenameTo = target;



try



{



//get response but ignore it



string str = GetStringResponse(ftp);



}



catch (Exception)



{



return false;



}



return true;



}



public bool FtpCreateDirectory(string dirpath)



{



//perform create



string URI = this.Hostname + AdjustDir(dirpath);



System.Net.FtpWebRequest ftp = GetRequest(URI);



//Set request to MkDir



ftp.Method = System.Net.WebRequestMethods.Ftp.MakeDirectory;



try



{



//get response but ignore it



string str = GetStringResponse(ftp);



}



catch (Exception)



{



return false;



}



return true;



}



public bool FtpDeleteDirectory(string dirpath)



{



//perform remove



string URI = this.Hostname + AdjustDir(dirpath);



System.Net.FtpWebRequest ftp = GetRequest(URI);



//Set request to RmDir



ftp.Method = System.Net.WebRequestMethods.Ftp.RemoveDirectory;



try



{



//get response but ignore it



string str = GetStringResponse(ftp);



}



catch (Exception)



{



return false;



}



return true;



}



#endregion



#region "private supporting fns"



//Get the basic FtpWebRequest object with the



//common settings and security



private FtpWebRequest GetRequest(string URI)



{



//create request



FtpWebRequest result = (FtpWebRequest)FtpWebRequest.Create(URI);



//Set the login details



result.Credentials = GetCredentials();



//Do not keep alive (stateless mode)



result.KeepAlive = true;



return result;



}



/// <summary>



/// Get the credentials from username/password



/// </summary>



private System.Net.ICredentials GetCredentials()



{



return new System.Net.NetworkCredential(Username, Password);



}



/// <summary>



/// returns a full path using CurrentDirectory for a relative file reference



/// </summary>



private string GetFullPath(string file)



{



if (file.Contains("/"))



{



return AdjustDir(file);



}



else



{



return this.CurrentDirectory + file;



}



}



/// <summary>



/// Amend an FTP path so that it always starts with /



/// </summary>



/// <param name="path">Path to adjust</param>



/// <returns></returns>



/// <remarks></remarks>



private string AdjustDir(string path)



{



return ((path.StartsWith("/")) ? "" : "/").ToString() + path;



}



private string GetDirectory(string directory)



{

string URI;



if (directory == "")



{



//build from current



URI = Hostname + this.CurrentDirectory;



_lastDirectory = this.CurrentDirectory;



}



else



{



if (!directory.StartsWith("/"))



{



throw (new ApplicationException("Directory should start with /"));



}



URI = this.Hostname + directory;



_lastDirectory = directory;



}



return URI;



}



//stores last retrieved/set directory



private string _lastDirectory = "";



/// <summary>



/// Obtains a response stream as a string



/// </summary>



/// <param name="ftp">current FTP request</param>



/// <returns>String containing response</returns>



/// <remarks>FTP servers typically return strings with CR and



/// not CRLF. Use respons.Replace(vbCR, vbCRLF) to convert



/// to an MSDOS string</remarks>



private string GetStringResponse(FtpWebRequest ftp)



{



//Get the result, streaming to a string



string result = "";



using (FtpWebResponse response = (FtpWebResponse)ftp.GetResponse())



{



long size = response.ContentLength;



using (Stream datastream = response.GetResponseStream())



{



using (StreamReader sr = new StreamReader(datastream))



{



result = sr.ReadToEnd();



sr.Close();



}



datastream.Close();



}



response.Close();



}



return result;



}



/// <summary>



/// Gets the size of an FTP request



/// </summary>



/// <param name="ftp"></param>



/// <returns></returns>



/// <remarks></remarks>



private long GetSize(FtpWebRequest ftp)



{



long size;



using (FtpWebResponse response = (FtpWebResponse)ftp.GetResponse())



{



size = response.ContentLength;



response.Close();



}



return size;



}



#endregion



#region "Properties"



private string _hostname;



/// <summary>



/// Hostname



/// </summary>



/// <value></value>



/// <remarks>Hostname can be in either the full URL format



/// ftp.myhost.com or just ftp.myhost.com



/// </remarks>



public string Hostname



{



get



{



if (_hostname.StartsWith("ftp://"))



{



return _hostname;



}



else



{



return "ftp://" + _hostname;



}



}



set



{



_hostname = value;



}



}



private string _username;



/// <summary>



/// Username property



/// </summary>



/// <value></value>



/// <remarks>Can be left blank, in which case 'anonymous' is

returned</remarks>



public string Username



{



get



{



return (_username == "" ? "anonymous" : _username);



}



set



{



_username = value;



}



}



private string _password;



public string Password



{



get



{



return _password;



}



set



{



_password = value;



}



}



/// <summary>



/// The CurrentDirectory value



/// </summary>



/// <remarks>Defaults to the root '/'</remarks>



private string _currentDirectory = "/";



public string CurrentDirectory



{



get



{



//return directory, ensure it ends with /



return _currentDirectory + ((_currentDirectory.EndsWith("/")) ? "" :

"/").ToString();



}



set



{



if (!value.StartsWith("/"))



{



throw (new ApplicationException("Directory should start with /"));



}



_currentDirectory = value;



}



}







#endregion



}



#endregion







#region "FTP file info class"



/// <summary>



/// Represents a file or directory entry from an FTP listing



/// </summary>



/// <remarks>



/// This class is used to parse the results from a detailed



/// directory list from FTP. It supports most formats of



/// </remarks>



public class FTPfileInfo



{



//Stores extended info about FTP file



#region "Properties"



public string FullName



{



get



{



return Path + Filename;



}



}



public string Filename



{



get



{



return _filename;



}



}



public string Path



{



get



{



return _path;



}



}



public DirectoryEntryTypes FileType



{



get



{



return _fileType;



}



}



public long Size



{



get



{



return _size;



}



}



public DateTime FileDateTime



{



get



{



return _fileDateTime;



}



}



public string Permission



{



get



{



return _permission;



}



}



public string Extension



{



get



{



int i = this.Filename.LastIndexOf(".");



if (i>= 0 && i < (this.Filename.Length - 1))



{



return this.Filename.Substring(i + 1);



}



else



{



return "";



}



}



}



public string NameOnly



{



get



{



int i = this.Filename.LastIndexOf(".");



if (i>0)



{



return this.Filename.Substring(0, i);



}



else



{



return this.Filename;



}



}



}



private string _filename;



private string _path;



private DirectoryEntryTypes _fileType;



private long _size;



private DateTime _fileDateTime;



private string _permission;



#endregion



/// <summary>



/// Identifies entry as either File or Directory



/// </summary>



public enum DirectoryEntryTypes



{



File,



Directory



}



/// <summary>



/// Constructor taking a directory listing line and path



/// </summary>



/// <param name="line">The line returned from the detailed directory

list</param>



/// <param name="path">Path of the directory</param>



/// <remarks></remarks>



public FTPfileInfo(string line, string path)



{



//parse line



Match m = GetMatchingRegex(line);



if (m == null)



{



//failed



throw (new ApplicationException("Unable to parse line: " + line));



}



else



{



_filename = m.Groups["name"].Value;



_path = path;



Int64.TryParse(m.Groups["size"].Value, out _size);



//_size = System.Convert.ToInt32(m.Groups["size"].Value);



_permission = m.Groups["permission"].Value;



string _dir = m.Groups["dir"].Value;



if (_dir != "" && _dir != "-")



{



_fileType = DirectoryEntryTypes.Directory;



}



else



{



_fileType = DirectoryEntryTypes.File;



}



try



{



_fileDateTime = DateTime.Parse(m.Groups["timestamp"].Value);



}



catch (Exception)



{



_fileDateTime = Convert.ToDateTime(null);



}



}



}



private Match GetMatchingRegex(string line)



{



Regex rx;



Match m;



for (int i = 0; i <= _ParseFormats.Length - 1; i++)



{



rx = new Regex(_ParseFormats[i]);



m = rx.Match(line);



if (m.Success)



{



return m;



}



}



return null;



}



#region "Regular expressions for parsing LIST results"



/// <summary>



/// List of REGEX formats for different FTP server listing formats



/// </summary>



/// <remarks>



/// The first three are various UNIX/LINUX formats, fourth is for MS FTP



/// in detailed mode and the last for MS FTP in 'DOS' mode.



/// I wish VB.NET had support for Const arrays like C# but there you go



/// </remarks>



private static string[] _ParseFormats = new string[] {



"(?<dir>[\\-d])(?<permission>([\\-r][\\-w][\\-xs]){3})\\s+\\d+\\s+\\w+\\s+\\w+\\s+(?<size>\\d+)\\s+(?<timestamp>\\w+\\s+\\d+\\s+\\d{4})\\s+(?<name>.+)",



"(?<dir>[\\-d])(?<permission>([\\-r][\\-w][\\-xs]){3})\\s+\\d+\\s+\\d+\\s+(?<size>\\d+)\\s+(?<timestamp>\\w+\\s+\\d+\\s+\\d{4})\\s+(?<name>.+)",



"(?<dir>[\\-d])(?<permission>([\\-r][\\-w][\\-xs]){3})\\s+\\d+\\s+\\d+\\s+(?<size>\\d+)\\s+(?<timestamp>\\w+\\s+\\d+\\s+\\d{1,2}:\\d{2})\\s+(?<name>.+)",



"(?<dir>[\\-d])(?<permission>([\\-r][\\-w][\\-xs]){3})\\s+\\d+\\s+\\w+\\s+\\w+\\s+(?<size>\\d+)\\s+(?<timestamp>\\w+\\s+\\d+\\s+\\d{1,2}:\\d{2})\\s+(?<name>.+)",



"(?<dir>[\\-d])(?<permission>([\\-r][\\-w][\\-xs]){3})(\\s+)(?<size>(\\d+))(\\s+)(?<ctbit>(\\w+\\s\\w+))(\\s+)(?<size2>(\\d+))\\s+(?<timestamp>\\w+\\s+\\d+\\s+\\d{2}:\\d{2})\\s+(?<name>.+)",



"(?<timestamp>\\d{2}\\-\\d{2}\\-\\d{2}\\s+\\d{2}:\\d{2}[Aa|Pp][mM])\\s+(?<dir>\\<\\w+\\>){0,1}(?<size>\\d+){0,1}\\s+(?<name>.+)"

};



#endregion



}



#endregion



#region "FTP Directory class"



/// <summary>



/// Stores a list of files and directories from an FTP result



/// </summary>



/// <remarks></remarks>



public class FTPdirectory : List<FTPfileInfo>



{







public FTPdirectory()



{



//creates a blank directory listing



}



/// <summary>



/// Constructor: create list from a (detailed) directory string



/// </summary>



/// <param name="dir">directory listing string</param>



/// <param name="path"></param>



/// <remarks></remarks>



public FTPdirectory(string dir, string path)



{



foreach (string line in dir.Replace("\n",

"").Split(System.Convert.ToChar('\r')))



{



//parse



if (line != "")



{



this.Add(new FTPfileInfo(line, path));



}



}



}



/// <summary>



/// Filter out only files from directory listing



/// </summary>



/// <param name="ext">optional file extension filter</param>



/// <returns>FTPdirectory listing</returns>



public FTPdirectory GetFiles(string ext)



{



return this.GetFileOrDir(FTPfileInfo.DirectoryEntryTypes.File, ext);



}



/// <summary>



/// Returns a list of only subdirectories



/// </summary>



/// <returns>FTPDirectory list</returns>



/// <remarks></remarks>



public FTPdirectory GetDirectories()



{



return this.GetFileOrDir(FTPfileInfo.DirectoryEntryTypes.Directory, "");



}



//internal: share use function for GetDirectories/Files



private FTPdirectory GetFileOrDir(FTPfileInfo.DirectoryEntryTypes type,

string ext)



{



FTPdirectory result = new FTPdirectory();



foreach (FTPfileInfo fi in this)



{



if (fi.FileType == type)



{



if (ext == "")



{



result.Add(fi);



}



else if (ext == fi.Extension)



{



result.Add(fi);



}



}



}



return result;



}



public bool FileExists(string filename)



{



foreach (FTPfileInfo ftpfile in this)



{



if (ftpfile.Filename == filename)



{



return true;



}



}



return false;



}



private const char slash = '/';



public static string GetParentDirectory(string dir)



{



string tmp = dir.TrimEnd(slash);



int i = tmp.LastIndexOf(slash);



if (i>0)



{



return tmp.Substring(0, i - 1);



}



else



{



throw (new ApplicationException("No parent for root"));



}



}



}



#endregion



}


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