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Unable to download the PDF file from URL

I need to download an .PDF file from a website : https://XXXXX/XXXX/XXXXXXX.pdf when user click's on link button. Below code is working fine in local but when I try to click on link button for downloading the file after deploying into server, First time it is working fire but next consecutive downloads, It is displaying as The XXXX.PDF download was interrupted or file cannot be downloaded.
try
{
string fullFileName =string.Empty;
LinkButton btn = (LinkButton)(sender);
string filepath = btn.CommandArgument;
string fileName = btn.Text;
if (fileName != null && !string.IsNullOrEmpty(fileName))
{
fullFileName = filePath +fileName ;
int bytesToRead = 10000;
// Buffer to read bytes in chunk size specified above
byte[] buffer = new Byte[bytesToRead];
//string fileName = System.IO.Path.GetFileName(fullFileName);
//Create a WebRequest to get the file
System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 | System.Net.SecurityProtocolType.Tls | (SecurityProtocolType)768/*TLS1.1*/ | (SecurityProtocolType)3072/*TLS1.2*/;
HttpWebRequest fileReq = (HttpWebRequest)HttpWebRequest.Create(fullFileName);
//Create a response for this request
HttpWebResponse fileResp = (HttpWebResponse)fileReq.GetResponse();
if (fileReq.ContentLength > 0)
fileResp.ContentLength = fileReq.ContentLength;
//Get the Stream returned from the response
stream = fileResp.GetResponseStream();
// prepare the response to the client. resp is the client Response
var resp = HttpContext.Current.Response;
//Indicate the type of data being sent
resp.ContentType = "application/PDF";
//Name the file
resp.AddHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
resp.AddHeader("Content-Length", fileResp.ContentLength.ToString());
int length;
do
{
// Verify that the client is connected.
if (resp.IsClientConnected)
{
// Read data into the buffer.
length = stream.Read(buffer, 0, bytesToRead);
// and write it out to the response's output stream
resp.OutputStream.Write(buffer, 0, length);
// Flush the data
resp.Flush();
//Clear the buffer
buffer = new Byte[bytesToRead];
}
else
{
// cancel the download if client has disconnected
length = -1;
}
} while (length > 0); //Repeat until no data is read
}
else
{
lblFile.Text = "File Name is missing";
lblFile.Visible = true;
}
}
catch (Exception ex)
{
}
finally
{
if (stream != null)
{
//Close the input stream
stream.Close();
}
}
Can someone please guide me why it is failing in server

Response.OutputStream.Write() Show data to browser Instead of Download

I use IHttpHandler to Download a file from Server.Everything works fine.
But it shows the data on browser instead of download it. I need to download the file from the server like we do download from other servers.
Could anyone suggest me, what should I do to download the file,
Or what is the convenient way to download a file(pdf,mp4 etc).
public void ProcessRequest(HttpContext context)
{
string strPathName = "";
if (context.Request.QueryString["fileName"] != null)
{
strPathName = context.Request.QueryString["fileName"].ToString();
}
string filename = context.Server.MapPath("~/MyPath/" + strPathName);
System.IO.Stream oStream = null;
oStream =
new System.IO.FileStream
(path: filename,
mode: System.IO.FileMode.Open,
share: System.IO.FileShare.Read,
access: System.IO.FileAccess.Read);
try
{
context.Response.ClearHeaders();
context.Response.Buffer = false;
context.Response.ContentType = "application/octet-stream";
context.Response.AddHeader("Content-Disposition", "attachment");
long lngFileLength = oStream.Length;
context.Response.AddHeader("Content-Length", lngFileLength.ToString());
long lngDataToRead = lngFileLength;
while (lngDataToRead > 0)
{
if (context.Response.IsClientConnected)
{
int intBufferSize = 8 * 1024;
byte[] bytBuffers =
new System.Byte[intBufferSize];
int intTheBytesThatReallyHasBeenReadFromTheStream =
oStream.Read(buffer: bytBuffers, offset: 0, count: intBufferSize);
context.Response.OutputStream.Write
(buffer: bytBuffers, offset: 0,
count: intTheBytesThatReallyHasBeenReadFromTheStream);
context.Response.Flush();
lngDataToRead =
lngDataToRead - intTheBytesThatReallyHasBeenReadFromTheStream;
}
else
{
lngDataToRead = -1;
}
}
}
catch { }
finally
{
if (oStream != null)
{
oStream.Close();
oStream.Dispose();
oStream = null;
}
context.Response.Close();
}
}

You can't directly download a file via ajax, it only returns the data into a JS variable in the page's code, instead of triggering a traditional request and download.
Your button needs to make a standard HTTP request, not an ajax call.

Download function failing with file size 1.35gb

I have this download function, and it's working great. BUT with a file with filesize of 1.35gb the download stops at 300 Mb, 382, 400mb or 1.27 Gb. What am I doing wrong? (The download function is made this way, because files need to be hidden, and may not be published on the website.)
public static void downloadFunction(string filename)
{
string filepath = #"D:\texts\New folder\DLfolder\" + filename;
string contentType = "application/x-newton-compatible-pkg";
Stream iStream = null;
// Buffer to read 10K bytes in chunk
//byte[] buffer = new Byte[10000];
// 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));
HttpContext.Current.Response.AddHeader("Content-Length", iStream.Length.ToString());
// 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();
}
}

You may have hit the request timeout. Take a note, if file stops downloading after some predetermined amount of time, like 60 or 300 seconds. If that is the case, you can configure timeouts in web.config of your application.

Program hangs on FtpWebResponse

First time poster, long-time reader. I have a really annoying problem thats been getting on my nerves. Ive got a program set up so I listen for new files on an FTP server, if theres a new file I download it. From there I work on some of the information in the file, etc. My problem comes when I run through my sequence the second time. That is, on the first file I download everything is totally fine, but as soon as a new file gets detected and my program tries downloading it, my program just hangs.
private static void DownloadFile(string s)
{
try
{
FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftp://blabla.com/"+s);
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = new NetworkCredential("xxx" ,"zzz");
using (FtpWebResponse partResponse = (FtpWebResponse)request.GetResponse())
{
Stream partReader = partResponse.GetResponseStream();
byte[] buffer = new byte[1024];
FileInfo fi = new FileInfo(path);
FileStream memStream = fi.Create();
while (true)
{
int bytesRead = partReader.Read(buffer, 0, buffer.Length - 1);
if (bytesRead == 0)
break;
memStream.Write(buffer, 0, bytesRead);
}
partResponse.Close();
memStream.Close();
}
Console.WriteLine(DateTime.Now + " file downloaded");
MoveFileToInProgress(s);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
The line it hangs on is this one:
using (FtpWebResponse partResponse = (FtpWebResponse)request.GetResponse())
The reason my method here is static is because Im just running it in a different project to test it.. My question here is, how come it only ever dies on the second file? Ive been staring myself blind for hours now!

I ran into this problem as well... try finishing your request first and then closing it before trying to retrieve the response. That worked for me (actually tried it after reading comment by MartinNielsen). Here is what I did.
// connect to the ftp site
FtpWebRequest ftpRequest = (FtpWebRequest)WebRequest.Create(ftpUri);
ftpRequest.Method = WebRequestMethods.Ftp.UploadFile;
ftpRequest.Credentials = new NetworkCredential(ftpUser, ftpPassword);
// setting proxy to null so that it does not go through the proxy
ftpRequest.Proxy = null;
// get file information
StreamReader fileStream = new StreamReader(filePath);
byte[] fileBytes = Encoding.UTF8.GetBytes(fileStream.ReadToEnd());
ftpRequest.ContentLength = fileBytes.Length;
fileStream.Close();
// open connection to ftp site
Stream ftpRequestStream = ftpRequest.GetRequestStream();
// write the file to the stream
ftpRequestStream.Write(fileBytes, 0, fileBytes.Length);
// close the stream
ftpRequestStream.Close();
// get the response from the server
FtpWebResponse ftpUploadResponse = (FtpWebResponse)ftpRequest.GetResponse();
string result = ftpUploadResponse.StatusDescription;
// close response
ftpUploadResponse.Close();
// return response to calling code
return result;
Here are a couple of the resources that I used when writing this code (won't let me post more than 2, there were more)
How to: Upload Files with FTP
Uploading a file -- "The requested URI is invalid for this FTP command"

I'm not expert on C# but I use this code to download files from my ftp:
public void Download(string filename)
{
// I try to download five times before crash
for (int i = 1; i < 5; i++)
{
try
{
FtpWebRequest ftp = (FtpWebRequest)FtpWebRequest.Create(Global.Path + "/" + filename);
ftp.Credentials = new NetworkCredential(User, Pass);
ftp.KeepAlive = false;
ftp.Method = WebRequestMethods.Ftp.DownloadFile;
ftp.UseBinary = true;
ftp.Proxy = null;
int buffLength = 2048;
byte[] buff = new byte[buffLength];
int contentLen;
string LocalDirectory = Application.StartupPath.ToString() + "/downloads/" + filename;
using (FileStream fs = new FileStream(LocalDirectory, FileMode.Create, FileAccess.Write, FileShare.None))
using (Stream strm = ftp.GetResponse().GetResponseStream())
{
contentLen = strm.Read(buff, 0, buffLength);
while (contentLen != 0)
{
fs.Write(buff, 0, contentLen);
contentLen = strm.Read(buff, 0, buffLength);
}
}
Process.Start(LocalDirectory);
break;
}
catch (Exception exc)
{
if (i == 5)
{
MessageBox.Show("Can't download, try number: " + i + "/5 \n\n Error: " + exc.Message,
"Problem downloading the file");
}
}
}
}
Tell me if it works for you :)

Upload a file with encoding using FTP in C#

The following code is good for uploading text files, but it fails to upload JPEG files (not completely - the file name is good but the image is corrupted):
private void up(string sourceFile, string targetFile)
{
try
{
string ftpServerIP = ConfigurationManager.AppSettings["ftpIP"];
string ftpUserID = ConfigurationManager.AppSettings["ftpUser"];
string ftpPassword = ConfigurationManager.AppSettings["ftpPass"];
//string ftpURI = "";
string filename = "ftp://" + ftpServerIP + "//" + targetFile;
FtpWebRequest ftpReq = (FtpWebRequest)WebRequest.Create(filename);
ftpReq.Method = WebRequestMethods.Ftp.UploadFile;
ftpReq.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
StreamReader stream = new StreamReader(sourceFile);
Byte[] b = System.Text.Encoding.UTF8.GetBytes(stream.ReadToEnd());
stream.Close();
ftpReq.ContentLength = b.Length;
Stream s = ftpReq.GetRequestStream();
s.Write(b, 0, b.Length);
s.Close();
System.Net.FtpWebResponse ftpResp = (FtpWebResponse)ftpReq.GetResponse();
MessageBox.Show(ftpResp.StatusDescription);
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
I have another solution that can upload a file:
private void Upload(string sourceFile, string targetFile)
{
string ftpUserID;
string ftpPassword;
string ftpServerIP;
ftpServerIP = ConfigurationManager.AppSettings["ftpIP"];
ftpUserID = ConfigurationManager.AppSettings["ftpUser"];
ftpPassword = ConfigurationManager.AppSettings["ftpPass"];
FileInfo fileInf = new FileInfo(sourceFile);
FtpWebRequest reqFTP;
// Create FtpWebRequest object from the Uri provided
reqFTP = (FtpWebRequest)(FtpWebRequest.Create(new Uri("ftp://" + ftpServerIP + "//" + targetFile)));
// Provide the WebPermission Credintials
reqFTP.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
// Bypass default lan settings
reqFTP.Proxy = null;
// 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
reqFTP.ContentLength = fileInf.Length;
// The buffer size is set to 2kb
int buffLength = 2048;
Byte[] buff;
buff = new byte[buffLength];
int contentLen;
// Opens a file stream (System.IO.FileStream) to read the file to be uploaded
FileStream fs = fileInf.OpenRead();
try
{
// Stream to which the file to be upload is written
Stream strm = reqFTP.GetRequestStream();
// Read from the file stream 2kb at a time
long filesize = fs.Length;
int i=0;
contentLen = fs.Read(buff, 0, buffLength);
// Till Stream content ends
while (contentLen != 0)
{
Application.DoEvents();
// Write Content from the file stream to the FTP Upload Stream
strm.Write(buff, 0, contentLen);
contentLen = fs.Read(buff, 0, buffLength);
i = i + 1;
//Double percentComp = (i * buffLength) * 100 / filesize;
//ProgressBar1.Value = (int)percentComp;
}
// Close the file stream and the Request Stream
strm.Close();
fs.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Upload Error");
}
}
But here I have the opposite problem - the picture is good, but the file name is corrupted.
I know it is because of the encoding, but I don't know how to make the bytes array have the desired encoding...

Try this bit:
private static void up(string sourceFile, string targetFile)
{
try
{
string ftpServerIP = ConfigurationManager.AppSettings["ftpIP"];
string ftpUserID = ConfigurationManager.AppSettings["ftpUser"];
string ftpPassword = ConfigurationManager.AppSettings["ftpPass"];
////string ftpURI = "";
string filename = "ftp://" + ftpServerIP + "//" + targetFile;
FtpWebRequest ftpReq = (FtpWebRequest)WebRequest.Create(filename);
ftpReq.UseBinary = true;
ftpReq.Method = WebRequestMethods.Ftp.UploadFile;
ftpReq.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
byte[] b = File.ReadAllBytes(sourceFile);
ftpReq.ContentLength = b.Length;
using (Stream s = ftpReq.GetRequestStream())
{
s.Write(b, 0, b.Length);
}
FtpWebResponse ftpResp = (FtpWebResponse)ftpReq.GetResponse();
if (ftpResp != null)
{
MessageBox.Show(ftpResp.StatusDescription);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}

You should be using a Stream to read binary files, not a StreamReader. StreamReader is designed to read text files only.

In your first code example, enable binary transfer: FtpWebRequest.UseBinary = true. Otherwise it will convert what it thinks are textual line endings between the various platform conventions (but are actually part of the image).

Your second snippet does it the right way. It uses FileStream, not StreamReader. StreamReader is only suitable for text files.

System.Text.Encoding.UTF8.GetBytes(stream.ReadToEnd());
Don't do this unless your stream's contents are text. Change your function to accept a boolean parameter "binary", and use the latter, working method if that flag is set.

If you have this problem: The requested FTP command is not supported when using HTTP
you need set proxy in Null or Nothing.
ftpReq.Proxy = null;
You can see this blog.
http://mycodetrip.com/2008/10/29/fix-for-error-the-requested-ftp-command-is-not-supported-when-using-http-proxy_118/comment-page-1/#comment-2825
Thanks.