Develop Reference

Download FTP using FtpWebRequest in Windows Form .Net

I have tried to download an FTP file using C# and have had various problems. What I want to achieve is to be able to show download progress in a progressBar. It is important that I use Windows Form and .Net.
I have tried two codes;
My first code works perfectly, that is, I can download the FTP file without problems.
CODE 1
FtpWebRequest dirFtp = ((FtpWebRequest)FtpWebRequest.Create(ficFTP));
dirFtp.KeepAlive = true;
dirFtp.UsePassive = UsePassive;
dirFtp.UseBinary = UseBinary;
// Los datos del usuario (credenciales)
NetworkCredential cr = new NetworkCredential(user, pass);
dirFtp.Credentials = cr;
FtpWebResponse response = (FtpWebResponse)dirFtp.GetResponse();
long size = (long)response.ContentLength;
Stream responseStream = response.GetResponseStream();
StreamReader reader = new StreamReader(responseStream);
using (FileStream writer = new FileStream(dirLocal, FileMode.Create))
{
int bufferSize = 2048;
int readCount;
byte[] buffer = new byte[2048];
readCount = responseStream.Read(buffer, 0, bufferSize);
while (readCount > 0)
{
writer.Write(buffer, 0, readCount);
readCount = responseStream.Read(buffer, 0, bufferSize);
}
}
lblDescarga.Text = "¡Downloaded!";
reader.Close();
response.Close();
Problem with this code
My problem with this code is that I can't get the size of the FTP file to be able to use the progressBar, In theory this section of code would tell me the size of my file but it always returns -1:
long size = (long)response.ContentLength;
As this did not work as I wanted, I made a post and people recommended this solution FtpWebRequest FTP download with ProgressBar:
CODE 2
try
{
const string url = "ftp://185.222.111.11:21/patch/archive.zip";
NetworkCredential credentials = new NetworkCredential("user", "pass");
// Query size of the file to be downloaded
WebRequest sizeRequest = WebRequest.Create(url);
sizeRequest.Credentials = credentials;
sizeRequest.Method = WebRequestMethods.Ftp.GetFileSize;
int size = (int)sizeRequest.GetResponse().ContentLength;
progressBar1.Invoke(
(MethodInvoker)(() => progressBar1.Maximum = size));
// Download the file
WebRequest request = WebRequest.Create(url);
request.Credentials = credentials;
request.Method = WebRequestMethods.Ftp.DownloadFile;
using (Stream ftpStream = request.GetResponse().GetResponseStream())
using (Stream fileStream = File.Create(#"C:\tmp\archive.zip"))
{
byte[] buffer = new byte[10240];
int read;
while ((read = ftpStream.Read(buffer, 0, buffer.Length)) > 0)
{
fileStream.Write(buffer, 0, read);
int position = (int)fileStream.Position;
progressBar1.Invoke(
(MethodInvoker)(() => progressBar1.Value = position));
}
}
}
catch (Exception e)
{
MessageBox.Show(e.Message);
}
Problem with this code
The problem with this code is when it gets to this point:
int size = (int) sizeRequest.GetResponse (). ContentLength;
Remote server error: (550) File not available (eg file not found or not accessed).
The truth is that it is impossible to tell that you do not have permission if code 1 works well. However I have the normal permissions in FTP, could someone give me an idea please?

File download in chunks in http-context response C#

I have a below scenario.
Client send request to Server-1 for file download
Server-1 send request to Server-2 for file.
To make this work I need to create a mechanism where once client send request to the Server-1, Server-1 will request to Server-2 which will send file as response output-stream in chunks. Server-1 will send this file chunks to client browser continuously as it keep receiving from server-2.
I have done code as below, theoretically it looks fine but still it is not working.
It is not downloading entire file in client browser, it seems like last chunk is not transferred to the Server-1 or it is not downloading to client browser from Server-1
Server-1 Code (Where client request for File download)
private void ProccesBufferedResponse(HttpWebRequest webRequest, HttpContext context)
{
char[] responseChars = null;
byte[] buffer = null;
if (webRequest == null)
logger.Error("Request string is null for Perfios Docs Download at ProccesBufferedResponse()");
context.Response.Buffer = false;
context.Response.BufferOutput = false;
try
{
WebResponse webResponse = webRequest.GetResponse();
context.Response.ContentType = "application/pdf";
context.Response.AddHeader("Content-disposition", webResponse.Headers["Content-disposition"]);
StreamReader responseStream = new StreamReader(webResponse.GetResponseStream());
while (!responseStream.EndOfStream)
{
responseChars = new char[responseStream.ToString().ToCharArray().Length];
responseStream.Read(responseChars, 0, responseChars.Length);
buffer = Encoding.ASCII.GetBytes(responseChars);
context.Response.Clear();
context.Response.OutputStream.Write(buffer, 0, buffer.Length);
context.Response.Flush();
}
}
catch (Exception ex)
{
throw;
}
finally
{
context.Response.Flush();
context.Response.End();
}
}
Server-2 Code (Where Server-1 will send request for file)
private void DownloadInstaPerfiosDoc(int CompanyID, string fileName, string Foldertype)
{
string folderPath;
string FilePath;
int chunkSize = 1024;
int startIndex = 0;
int endIndex = 0;
int length = 0;
byte[] bytes = null;
DirectoryInfo dir;
folderPath = GetDocumentDirectory(CompanyID, Foldertype);
FilePath = folderPath + "\\" + fileName;
dir = new DirectoryInfo(folderPath);
HttpContext.Current.Response.Buffer = false;
HttpContext.Current.Response.BufferOutput = false;
if (dir.Exists && dir.GetFiles().Length > 0)
{
foreach (var file in dir.GetFiles(fileName))
{
FilePath = folderPath + "\\" + file.Name;
FileStream fsReader = new FileStream(FilePath, FileMode.Open, FileAccess.Read);
HttpContext.Current.Response.ContentType = "application/pdf";
HttpContext.Current.Response.AddHeader("Content-disposition", string.Format("attachment; filename = \"{0}\"", fileName));
int totalChunks = (int)Math.Ceiling((double)fsReader.Length / chunkSize);
for (int i = 0; i < totalChunks; i++)
{
startIndex = i * chunkSize;
if (startIndex + chunkSize > fsReader.Length)
endIndex = (int)fsReader.Length;
else
endIndex = startIndex + chunkSize;
length = (int)endIndex - startIndex;
bytes = new byte[length];
fsReader.Read(bytes, 0, bytes.Length);
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.OutputStream.Write(bytes, 0, bytes.Length);
HttpContext.Current.Response.Flush();
}
}
}
}
Please help me to resolve this issue.

It is possible and feasible. I'll give a pseudo procedure for you to understand the overall idea.
Server1
download action gets hit
create a request to server2
get the response stream of your server2 request
read the response stream in desired chunk sizes until it's consumed completely
write each chunk (as soon as you read) to current response stream
Server2
download action gets hit
write your stream onto your current response stream however you like

Can't download complete image file from skydrive using REST API

I'm working on a quick wrapper for the skydrive API in C#, but running into issues with downloading a file. For the first part of the file, everything comes through fine, but then there start to be differences in the file and shortly thereafter everything becomes null. I'm fairly sure that it's just me not reading the stream correctly.
This is the code I'm using to download the file:
public const string ApiVersion = "v5.0";
public const string BaseUrl = "https://apis.live.net/" + ApiVersion + "/";
public SkyDriveFile DownloadFile(SkyDriveFile file)
{
string uri = BaseUrl + file.ID + "/content";
byte[] contents = GetResponse(uri);
file.Contents = contents;
return file;
}
public byte[] GetResponse(string url)
{
checkToken();
Uri requestUri = new Uri(url + "?access_token=" + HttpUtility.UrlEncode(token.AccessToken));
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(requestUri);
request.Method = WebRequestMethods.Http.Get;
WebResponse response = request.GetResponse();
Stream responseStream = response.GetResponseStream();
byte[] contents = new byte[response.ContentLength];
responseStream.Read(contents, 0, (int)response.ContentLength);
return contents;
}
This is the image file I'm trying to download
And this is the image I am getting
These two images lead me to believe that I'm not waiting for the response to finish coming through, because the content-length is the same as the size of the image I'm expecting, but I'm not sure how to make my code wait for the entire response to come through or even really if that's the approach I need to take.
Here's my test code in case it's helpful
[TestMethod]
public void CanUploadAndDownloadFile()
{
var api = GetApi();
SkyDriveFolder folder = api.CreateFolder(null, "TestFolder", "Test Folder");
SkyDriveFile file = api.UploadFile(folder, TestImageFile, "TestImage.png");
file = api.DownloadFile(file);
api.DeleteFolder(folder);
byte[] contents = new byte[new FileInfo(TestImageFile).Length];
using (FileStream fstream = new FileStream(TestImageFile, FileMode.Open))
{
fstream.Read(contents, 0, contents.Length);
}
using (FileStream fstream = new FileStream(TestImageFile + "2", FileMode.CreateNew))
{
fstream.Write(file.Contents, 0, file.Contents.Length);
}
Assert.AreEqual(contents.Length, file.Contents.Length);
bool sameData = true;
for (int i = 0; i < contents.Length && sameData; i++)
{
sameData = contents[i] == file.Contents[i];
}
Assert.IsTrue(sameData);
}
It fails at Assert.IsTrue(sameData);

This is because you don't check the return value of responseStream.Read(contents, 0, (int)response.ContentLength);. Read doesn't ensure that it will read response.ContentLength bytes. Instead it returns the number of bytes read. You can use a loop or stream.CopyTo there.
Something like this:
WebResponse response = request.GetResponse();
MemoryStream m = new MemoryStream();
response.GetResponseStream().CopyTo(m);
byte[] contents = m.ToArray();

As LB already said, you need to continue to call Read() until you have read the entire stream.
Although Stream.CopyTo will copy the entire stream it does not ensure that read the number of bytes expected. The following method will solve this and raise an IOException if it does not read the length specified...
public static void Copy(Stream input, Stream output, long length)
{
byte[] bytes = new byte[65536];
long bytesRead = 0;
int len = 0;
while (0 != (len = input.Read(bytes, 0, Math.Min(bytes.Length, (int)Math.Min(int.MaxValue, length - bytesRead)))))
{
output.Write(bytes, 0, len);
bytesRead = bytesRead + len;
}
output.Flush();
if (bytesRead != length)
throw new IOException();
}

Download function not showing total size of file, while downloading

protected void downloadFunction(string filename)
{
string filepath = #"D:\XtraFiles\" + filename;
string contentType = "application/x-newton-compatible-pkg";
Stream iStream = null;
// Buffer to read 1024K bytes in chunk
byte[] buffer = new Byte[1048576];
// Length of the file:
int length;
// Total bytes to read:
long dataToRead;
try
{
// Open the file.
iStream = new FileStream(filepath, FileMode.Open, FileAccess.Read, FileShare.Read);
// Total bytes to read:
dataToRead = iStream.Length;
HttpContext.Current.Response.ContentType = contentType;
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(filename, System.Text.Encoding.UTF8));
// Read the bytes.
while (dataToRead > 0)
{
// Verify that the client is connected.
if (HttpContext.Current.Response.IsClientConnected)
{
// Read the data in buffer.
length = iStream.Read(buffer, 0, 10000);
// Write the data to the current output stream.
HttpContext.Current.Response.OutputStream.Write(buffer, 0, length);
// Flush the data to the HTML output.
HttpContext.Current.Response.Flush();
buffer = new Byte[10000];
dataToRead = dataToRead - length;
}
else
{
//prevent infinite loop if user disconnects
dataToRead = -1;
}
}
}
catch (Exception ex)
{
// Trap the error, if any.
HttpContext.Current.Response.Write("Error : " + ex.Message + "<br />");
HttpContext.Current.Response.ContentType = "text/html";
HttpContext.Current.Response.Write("Error : file not found");
}
finally
{
if (iStream != null)
{
//Close the file.
iStream.Close();
}
HttpContext.Current.Response.End();
HttpContext.Current.Response.Close();
}
}
My donwload function is working perfect, but when users are downloading the browser cant see the total file size of the download.
So now the browser says eq. Downloading 8mb of ?, insted of Downloading 8mb of 142mb.
What have i missed?

The Content-Length header seems to be what you are missing.
If you set this the browser will then know how much to expect. Otherwise it will just keep going til you stop sending data and it won't know how long it is until the end.
Response.AddHeader("Content-Length", iStream.Length);
You may also be interested in Response.WriteFile whcih can provide an easier way to send a file to a client without having to worry about streams yourself.

You need to send a ContentLength-Header:
HttpContext.Current.Response.AddHeader(HttpRequestHeader.ContentLength, iStream.Length);

Multiple threads uploading files to filezilla ftp server returns error 550 File unavailable

Problem: When i ftp upload only one file at a time, the files are uploaded fine, But when i use multiple Background workers to upload files to ftp server i get exception:
ex {"The remote server returned an error: (550) File unavailable
(e.g., file not found, no access)."} System.Exception
{System.Net.WebException}
And only Some of the files get uploaded. I am pretty sure the file exits at that location, infact in another run the file it was complaining about that does not exist is downloaded but the error shifts on another file.
Code Description:
In below code i am downloading a file from one ftp server and putting it on another. This code is inside a BackgroundsWorker_DoWork Method. Background Workers are being created inside a loop.
void imageDownloadWorker_DoWork(object sender, DoWorkEventArgs e)
{
string[] ftpInfo = (string[])e.Argument;
try
{
///////////////////////////Downloading///////////////////////////////////////
string uri = String.Format("ftp://{0}/{1}/images/{2}", ftpInfo[1], ftpInfo[2], ftpInfo[5]);
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(uri);
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.UseBinary = true;
request.Credentials = new NetworkCredential(ftpInfo[3], ftpInfo[4]);
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
Stream ftpStream = response.GetResponseStream();
long cl = response.ContentLength;
int bufferSize = 4096;
int readCount = 0;
byte[] buffer = new byte[bufferSize];
MemoryStream memStream = new MemoryStream();
readCount = ftpStream.Read(buffer, 0, bufferSize);
while (readCount > 0)
{
memStream.Write(buffer, 0, readCount);
readCount = ftpStream.Read(buffer, 0, bufferSize);
}
response.Close();
///////////////////////////Uploading///////////////////////////////////////
string uri1 = String.Format("ftp://{0}/{1}/{2}", "127.0.0.1", string.Empty, ftpInfo[5]);
FtpWebRequest request1 = (FtpWebRequest)WebRequest.Create(uri1);
request1.Credentials = new NetworkCredential("user", "password");
request1.KeepAlive = false;
request1.Method = WebRequestMethods.Ftp.UploadFile;
request1.UseBinary = true;
request1.ContentLength = memStream.Length;
int buffLength = 4096;
byte[] buff = new byte[buffLength];
int contentLen;
// Stream to which the file to be upload is written
Stream strm = request1.GetRequestStream();
memStream.Seek(0, SeekOrigin.Begin);
contentLen = memStream.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 = memStream.Read(buff, 0, buffLength);
}
// Close the file stream and the Request Stream
strm.Close();
ftpStream.Close();
memStream.Close();
}
catch(Exception ex)
{
MessageBox.Show("While Downloading File " + ftpInfo[5] + " " + ex.ToString(), "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
e.Result = null;
return;
}
Related Thread
Edit:
In File Zilla Server there is an option General Settings>Perfomance Settings>Number of Threads i have set that to 20 it didnt make any difference.

There maybe nothing wrong with your code. That error is a Permissions error.

Complete stab in the dark, but does the upload target server have a connection per IP limit? If so you may be falling foul of this by exceeding the concurrent connection limit from a single IP address.