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download log file from ftp server to stream and get the last line of the log file using c#

I am trying to download a log file to my program without save it to my local machine, and get the last line of the log.
can anyone send me an example of it or look at the code and tell me what is wrong.
thanks
FileStream outputStream = new FileStream(uri, FileMode.Create);
request = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.UseBinary = true;
request.Credentials = new NetworkCredential(userName, Password);
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
Stream ftpStream = response.GetResponseStream();
long cl = response.ContentLength;
int readCount;
readCount = ftpStream.Read(b, 0, b.Length);
while (readCount > 0)
{
outputStream.Write(b, 0, readCount);
readCount = ftpStream.Read(b, 0, b.Length);
}
temp2 = System.Text.Encoding.UTF8.GetString(b);
temp1 = temp2.Split(new string[] { "\r\n" }, StringSplitOptions.RemoveEmptyEntries);
LastItem = temp1.Last();
ftpStream.Close();
outputStream.Close();
response.Close();

How to properly disconnect from FTP server with FtpWebRequest

I've created a ftp client that connects several times during the day to retrieve log files from a FTP server.
The Problem is that after a few hours I am getting an error message from the FTP server (-421 session limit reached..). When I check the connections with netstat, I can see several 'ESTABLISHED' connections to the server even though I've "closed" the connection.
When I try to do the same over the command line or FileZilla, the connections are properly closed.
ftpRequest = (FtpWebRequest)FtpWebRequest.Create(host + "/" + remoteFile);
ftpRequest.Credentials = new NetworkCredential(user, pass);
ftpRequest.UseBinary = true;
ftpRequest.UsePassive = true;
ftpRequest.KeepAlive = true;
ftpRequest.Method = WebRequestMethods.Ftp.DownloadFile;
ftpResponse = (FtpWebResponse)ftpRequest.GetResponse();
ftpStream = ftpResponse.GetResponseStream();
FileStream localFileStream = new FileStream(localFile, FileMode.Create);
int bytesRead = ftpStream.Read(byteBuffer, 0, bufferSize);
/* Resource Cleanup */
localFileStream.Close();
ftpStream.Close();
ftpResponse.Close();
ftpRequest = null;
How can I close/disconnect the connection properly? Did I forget anything?

Try and set the FtpWebRequest.KeepAlive property to false. If KeepAlive is set to false, then the control connection to the server will be closed when the request completes.
ftpWebRequest.KeepAlive = false;

Have you tried wrapping your response in a using statement?
using (FtpWebResponse response = request.GetResponse() as FtpWebResponse)
{
using (Stream responseStream = response.GetResponseStream())
{
using (StreamReader streamReader = new StreamReader(responseStream))
{
string responseString = streamReader.ReadToEnd();
Byte[] buffer = Encoding.UTF8.GetBytes(responseString);
memoryStream = new MemoryStream(buffer);
}
responseStream.Close();
}
response.Close();
}

FTP:Unable to write data to the transport connection: An existing connection was forcibly closed by the remote host

I'm newbie to FTP.I am trying to write to a file in FTP using StreamWriter.Once after writing to the file,i dont want to close the stream as i have some work which has to be done.Later after some 1 hour,if i try to write using the same streamWriter i get the above error.
Below is my code snippet
public void WriteToFTP()
{
bool isConnectionEstablished = false;
StreamWriter stream = null;
try
{
for (int i = 1; i < 5; i++)
{
string message = string.Format("File - {0}.", i.ToString());
if (!isConnectionEstablished)
{
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(new Uri("My FTP path"));
request.Credentials = new NetworkCredential("asdf", "asdf#123");
request.Proxy = null;
request.UseBinary = true;
request.ConnectionGroupName = string.Empty;
request.UsePassive = true;
request.EnableSsl = false;
isConnectionEstablished = true;
stream = new StreamWriter(request.GetRequestStream()) { AutoFlush = true };
}
stream.WriteLine(message);//Here i am getting the error for the i = 2(after doing my work)
//Doing work which may take more than 1 hour.
}
}
catch (Exception exe)
{
//The Error "Unable to write data to the transport connection: An existing connection was forcibly closed by the remote host" is being caught here.
}
finally
{
if (stream != null)
stream.Close();
}
}

you must set timout to infinity,-1 is the value for infinity, see this example:
FtpWebRequest reqFTP;
string fileName = #"c:\downloadDir\localFileName.txt";
FileInfo downloadFile = new FileInfo(fileName);
string uri = "ftp://ftp.myftpsite.com/ftpDir/remoteFileName.txt";
FileStream outputStream = new FileStream(fileName, FileMode.Append);
reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
reqFTP.Method = WebRequestMethods.Ftp.DownloadFile;
reqFTP.UseBinary = true;
reqFTP.KeepAlive = false;
reqFTP.Timeout = -1;
reqFTP.UsePassive = true;
reqFTP.Credentials = new NetworkCredential("userName", "passWord");
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);
Console.WriteLine("Connected: Downloading File");
while (readCount > 0)
{
outputStream.Write(buffer, 0, readCount);
readCount = ftpStream.Read(buffer, 0, bufferSize);
Console.WriteLine(readCount.ToString());
}
ftpStream.Close();
outputStream.Close();
response.Close();
Console.WriteLine("Downloading Complete");

FTP request to server can not connect remote server

I found a number of similar articles here but did not manage to solve my problem still.
I am trying to upload a text file to an ftp server. I used a number of methods and all of them i get same error : "Can not connect to remote server"
Method1 :
filename is the full path where the file is located
private string Upload(string ftpServer, string userName, string password, string filename)
{
string reply = "Success";
try
{
using (System.Net.WebClient client = new System.Net.WebClient()) //System.Net.WebClient client = new System.Net.WebClient()
{
client.Credentials = new System.Net.NetworkCredential(userName, password);
client.Proxy = new WebProxy();
FileInfo fi = new FileInfo(filename);
client.UploadFile(ftpServer + "//" + fi.Name, "STOR", filename);
}
}
catch (Exception ex)
{
reply = ex.Message;
}
return reply;
}
Method2:
filename = "D:\folder\file.txt"
public static void uploadFileUsingFTP(string filename)
{
FileInfo fileInf = new FileInfo(filename);
string uri = "ftp://" + serverIP + "/" + fileInf.Name;
FtpWebRequest reqFTP;
// Create FtpWebRequest object from the Uri provided
reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri(uri));
reqFTP.Proxy = null;
// Provide the WebPermission Credintials
reqFTP.Credentials = new NetworkCredential(user, pass);
// By default KeepAlive is true, where the control connection is not closed
// after a command is executed.
reqFTP.KeepAlive = false;
// Specify the command to be executed.
reqFTP.Method = WebRequestMethods.Ftp.UploadFile;
// Specify the data transfer type.
reqFTP.UseBinary = true;
// Notify the server about the size of the uploaded file
FileStream fs = File.OpenRead(filename);
reqFTP.ContentLength = fileInf.Length;
// The buffer size is set to 2kb
int buffLength = Convert.ToInt32(fs.Length);
byte[] buff = new byte[buffLength];
int contentLen;
try
{
// Stream to which the file to be upload is written
Stream strm = reqFTP.GetRequestStream();
// Read from the file stream 2kb at a time
contentLen = fs.Read(buff, 0, buffLength);
// Till Stream content ends
while (contentLen != 0)
{
// Write Content from the file stream to the FTP Upload Stream
strm.Write(buff, 0, contentLen);
contentLen = fs.Read(buff, 0, buffLength);
}
// Close the file stream and the Request Stream
strm.Close();
fs.Close();
}
catch (Exception ex)
{
string s = ex.Message;
}
}
Method3:
public static void Sample(string filename)
{
// Get the object used to communicate with the server.
FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftp://serverip/"); //test.htm
request.Method = WebRequestMethods.Ftp.UploadFile;
// This example assumes the FTP site uses anonymous logon.
request.Credentials = new NetworkCredential (user,passs);
try
{
// Copy the contents of the file to the request stream.
StreamReader sourceStream = new StreamReader(filename);
byte[] fileContents = Encoding.UTF8.GetBytes(sourceStream.ReadToEnd());
sourceStream.Close();
request.ContentLength = fileContents.Length;
request.Proxy = null;
Stream requestStream = request.GetRequestStream();
requestStream.Write(fileContents, 0, fileContents.Length);
requestStream.Close();
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
Console.WriteLine("Upload File Complete, status {0}", response.StatusDescription);
response.Close();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
Console.ReadLine();
}
Using each of them results in the same problem and yes i am able to connect to the ftp by using filezilla and also transfer files.
I know that i must be missing something very stupid but it is taking me so much time.
Any suggestion will be appreaciated.

Connection problems can be a nuisance to sort out. A tool like WireShark can be a big help in tracking down problems, e.g. when trying active vs. passive mode FTP transfers.
I've been using the following code with good results:
bool result = false;
long length = 0;
// Set up the FTP upload.
// The URI for the request specifies the protocol, the server and the filename.
FtpWebRequest ftpRequest = (FtpWebRequest)WebRequest.Create("ftp://" + ftpServerUrl + "/" + targetFilename);
ftpRequest.EnableSsl = false;
ftpRequest.KeepAlive = true;
ftpRequest.ReadWriteTimeout = ftpTimeout; // To perform an individual read or write.
ftpRequest.Timeout = ftpTimeout; // To establish a connection or start an operation.
ftpRequest.Credentials = new NetworkCredential(ftpUsername, ftpPassword);
ftpRequest.Method = WebRequestMethods.Ftp.UploadFile;
ftpRequest.UseBinary = true;
ftpRequest.UsePassive = true;
// Upload the file.
using (FileStream fileStream = File.OpenRead(filename))
{
using (Stream ftpStream = ftpRequest.GetRequestStream())
{
fileStream.CopyTo(ftpStream);
length = fileStream.Length;
ftpStream.Close();
}
FtpWebResponse ftpResponse = (FtpWebResponse)ftpRequest.GetResponse();
if (ftpResponse.StatusCode == FtpStatusCode.ClosingData)
result = true;
else
throw new Exception(ftpResponse.StatusDescription + " (" + ftpResponse.StatusCode + ")");
ftpResponse.Close();
}

Have already replied in another thread, however repeating here as well. I faced the same issue, here was my solution.
request.Credentials = new NetworkCredential(
usernameVariable.Normalize(),passwordVariable.Normalize(),domainVariable.Normalize());
Details can be found here
Hope it helps someone.

Add the following in your web.config to have your FtpWebRequest use the default proxy
<defaultProxy enabled="true" useDefaultCredentials="true">
</defaultProxy>

How to download FTP files with automatic resume in case of disconnect

I can download FTP files, but the download code does not have a resume facility and multi part files download. Because there are file larger than 500 MB, I can't download them continuously, because the connection gets closed and it starts download from beginning. I wanted my code a resume facility if it gets disconnected.
The code I am using is:
public string[] GetFileList()
{
string[] downloadFiles;
StringBuilder result = new StringBuilder();
FtpWebRequest reqFTP;
try
{
reqFTP = (FtpWebRequest)FtpWebRequest.Create(
new Uri("ftp://" + ftpServerIP + "/"));
reqFTP.UseBinary = true;
reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
reqFTP.Method = WebRequestMethods.Ftp.ListDirectory;
WebResponse response = reqFTP.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream());
//MessageBox.Show(reader.ReadToEnd());
string 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();
//MessageBox.Show(response.StatusDescription);
return result.ToString().Split('\n');
}
catch (Exception ex)
{
System.Windows.Forms.MessageBox.Show(ex.Message);
downloadFiles = null;
return downloadFiles;
}
}
private void Download(string filePath, string fileName)
{
FtpWebRequest reqFTP;
try
{
//filePath = <<The full path where the file is to be created.>>,
//fileName = <<Name of the file to be created
// (Need not be the name of the file on FTP server).>>
FileStream outputStream =
new FileStream(filePath + "\\" + fileName, FileMode.Create);
reqFTP = (FtpWebRequest)FtpWebRequest.Create(
new Uri("ftp://" + ftpServerIP + "/" + 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)
{
MessageBox.Show(ex.Message);
}
}

Before you start downloading check for the existence of the file on the local filesystem. If it exists, then get the size and use that for the ContentOffset member of the FtpWebRequest object. This functionality may not be supported by the FTP server, though.

A native implementation of FTP download resumption using the FtpWebRequest:
bool resume = false;
do
{
try
{
FileMode mode = resume ? FileMode.Append : FileMode.Create;
resume = false;
using (Stream fileStream = File.Open(#"C:\local\path\file.dat", mode))
{
var url = "ftp://ftp.example.com/remote/path/file.dat";
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(url);
request.Credentials = new NetworkCredential("username", "password");
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.ContentOffset = fileStream.Position;
using (Stream ftpStream = request.GetResponse().GetResponseStream())
{
ftpStream.CopyTo(fileStream);
}
}
}
catch (WebException)
{
resume = true;
}
}
while (resume);
Or use an FTP library that can resume the transfer automatically.
For example WinSCP .NET assembly does. With it, a resumable download is as trivial as:
// Setup session options
var sessionOptions = new WinSCP.SessionOptions
{
Protocol = Protocol.Ftp,
HostName = "ftp.example.com",
UserName = "user",
Password = "mypassword"
};
using (var session = new Session())
{
// Connect
session.Open(sessionOptions);
// Resumable download
session.GetFileToDirectory("/home/user/file.zip", #"C:\path");
}
(I'm the author of WinSCP)