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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

Failed to download files when deployed to Azure App Service

Large file download code found running on IIS.
But it stops at Azure AppService.
The file will download well and then stop when it reaches 1 GB.
Is there a problem with Azure App Service settings?
Please let me know what the problem is.
This is the ashx file code.
public void ProcessRequest(HttpContext context)
{
Stream stream = null;
int bytesToRead = 10000;
byte[] buffer = new Byte[bytesToRead];
string Url = context.Request.QueryString["Url"];
string FileName = HttpUtility.UrlEncode(context.Request.QueryString["FileName"]).Replace("+","%20");
try
{
HttpWebRequest fileReq = (HttpWebRequest)HttpWebRequest.Create(Url);
HttpWebResponse fileResp = (HttpWebResponse)fileReq.GetResponse();
if (fileReq.ContentLength > 0)
fileResp.ContentLength = fileReq.ContentLength;
stream = fileResp.GetResponseStream();
var resp = HttpContext.Current.Response;
resp.ContentType = "application/octet-stream";
resp.AddHeader("Content-Disposition", "attachment; filename=\"" + FileName + "\"");
resp.AddHeader("Content-Length", fileResp.ContentLength.ToString());
int length;
do
{
if (resp.IsClientConnected)
{
length = stream.Read(buffer, 0, bytesToRead);
resp.OutputStream.Write(buffer, 0, length);
resp.Flush();
buffer = new Byte[bytesToRead];
}
else
{
// cancel the download if client has disconnected
length = -1;
}
} while (length > 0); //Repeat until no data is read
}
finally
{
if (stream != null)
{
//Close the input stream
stream.Close();
}
}
}

To be honest, I didn't get any trouble using your code to download large files more than 1GB, even after publishing to Azure.
First, httpWebRequest doesn't not has any artificial size limit. I was wondering if you should consider other code to download, because it's not convenient if we couldn't see the details about the error log, and the download process.
Here is a issue might inspire you: C# - Is there a limit to the size of an httpWebRequest stream?
If you want try another code, try this:
static void Main(string[] args)
{
HttpWebRequestDownload hDownload = new HttpWebRequestDownload();
string downloadUrl = "http://speedtest.tele2.net/10MB.zip";
hDownload.DownloadProgressChanged += HDownloadOnDownloadProgressChanged;
hDownload.DownloadFileCompleted += delegate(object o, EventArgs args)
{
Debug.WriteLine("Download finished and saved to: "+hDownload.downloadedFilePath);
};
hDownload.Error += delegate(object o, string errMessage) { Debug.WriteLine("Error has occured !! => "+errMessage); };
hDownload.DownloadFile(downloadUrl);
}
private void HDownloadOnDownloadProgressChanged(object sender, HttpWebRequestDownload.ProgressEventArgs e)
{
Debug.WriteLine("progress: "+e.TransferredBytes+" => "+e.TransferredPercents);
}

Unable to get full image from server

I have a C# windows form application which downloads file from a url(asp.net application) but it is not returning full image lets say image is of 780kb the file that windows form creates is 381 bytes exactly.
I am not able to figure out the issue. Please help.
The code i am using for download is:
public bool getFileFromURL(string url, string filename)
{
long contentLength = 0;
Stream stream = null;
try
{
WebRequest req = WebRequest.Create(url);
WebResponse response = req.GetResponse();
stream = response.GetResponseStream();
contentLength = response.ContentLength;
// Transfer the file
byte[] buffer = new byte[10 * 1024]; // 50KB at a time
int numBytesRead = 0;
long totalBytesRead = 0;
using (FileStream fileStream = new FileStream(filename, FileMode.Create))
{
using (BinaryWriter fileWriter = new BinaryWriter(fileStream))
{
while (stream.CanRead)
{
numBytesRead = stream.Read(buffer, 0, buffer.Length);
if (numBytesRead == 0) break;
totalBytesRead += numBytesRead;
fileWriter.Write(buffer, 0, numBytesRead);
}
fileWriter.Close();
}
fileStream.Close();
}
stream.Close();
response.Close();
req.Abort();
return true;
}
catch (Exception)
{
return false;
}
}
This is my asp.net app code:
using (PortalEntities db = new PortalEntities())
{
PortalModel.Command command = db.Commands.SingleOrDefault(c => c.id == id);
var filePath = Server.MapPath("~/Uploads/"+command.arguments);
if (!File.Exists(filePath))
return;
var fileInfo = new System.IO.FileInfo(filePath);
Response.ContentType = "image/jpg";
Response.AddHeader("Content-Disposition", String.Format("attachment;filename=\"{0}\"", filePath));
Response.AddHeader("Content-Length", fileInfo.Length.ToString());
Response.WriteFile(filePath);
Response.End();
}

That's an awful lot of code to write some bytes out to a file from a web response. How about something like this (.NET 4+):
public static bool GetFileFromURL(string url, string filename)
{
try
{
var req = WebRequest.Create(url);
using (Stream output = File.OpenWrite(filename))
using (WebResponse res = req.GetResponse())
using (Stream s = res.GetResponseStream())
s.CopyTo(output);
return true;
}
catch
{
return false;
}
}

You can download image in more elegant way, it was discussed before here Unable to locate FromStream in Image class
And use File.WriteAllBytes Method to save the byte array as a file, more info at
http://msdn.microsoft.com/en-us/library/system.io.file.writeallbytes(v=vs.110).aspx
So all your client code can be replaced with
public void getFileFromURL(string url, string filename)
{
using (var webClient = new WebClient())
{
File.WriteAllBytes(filename,webClient.DownloadData(url));
}
}

Dude, why are you not using WebClient.DownloadFileAsync?
private void DownloadFile(string url, string path)
{
using (var client = new System.Net.WebClient())
{
client.DownloadFileAsync(new Uri(url), path);
}
}
That's pretty much it, but this method can't download over 2GB. But i don't think the image is that big xD.
Hope it helps!

IIS7 buffer size limit

My problem happens when trying to download a video file via http request
in the following operating systems using IIS7:
win2008 32Bit, Win2008 R2 64Bit
Currently works fine on: win2003 , vista64 (IIS6)
Problem description:
When users request a file larger than 256mb via C# they get a limited file, even when
using Content-Length param it seems that the file get the right size but not the full
content.
When requesting the URL of the file, I get the full file, the problem occurs only via
the C# script, also the C# response that the full buffer was sent to the user.
I've changed the IIS7 settings in the article:
http://blog.twinharbor.com/2011/07/28/fixing-iis7-maximum-upload-size/
and still it doesn't work.
Also, there are no remarks or errors anywhere.
Please find a sample of my code:
var context = System.Web.HttpContext.Current;
context.Response.ContentEncoding = Encoding.GetEncoding("windows-1255");
context.Response.HeaderEncoding = Encoding.GetEncoding("UTF-8");
context.Response.Charset = "utf-8";
System.IO.Stream iStream = null;
// Buffer to read 100K bytes in chunk:
byte[] buffer = new Byte[100000];
// Length of the file:
int length=0;
// Total bytes to read:
long dataToRead=0;
// Identify the file to download including its path.
string filepath = u.Trim(BigFile);
// Identify the file name.
string filename = System.IO.Path.GetFileName(filepath);
Start.Value = u.Time();
try
{
iStream = new System.IO.FileStream(filepath, System.IO.FileMode.Open, System.IO.FileAccess.Read, System.IO.FileShare.Read);
dataToRead = iStream.Length;
context.Response.Charset = "";
context.Response.ContentType = "application/octet-stream";
context.Response.AddHeader("Content-Disposition", "attachment; filename=" + filename);
context.Response.AddHeader("Content-Length", dataToRead.ToString());
while (dataToRead > 0)
{
if (context.Response.IsClientConnected)
{
length = iStream.Read(buffer, 0, 100000);
context.Response.OutputStream.Write(buffer, 0, length);
context.Response.Flush();
buffer = new Byte[100000];
dataToRead = dataToRead - length;
}
else
{
dataToRead = -1;
}
}
}
catch (Exception ex)
{
context.Response.Write("Error : " + ex.Message);
}
finally
{
if (iStream != null)
{
iStream.Close();
}
context.Response.Close();
}
I'll appericiate your help.
Thanks.

ASP.NET C# OutofMemoryException On Large File Upload

I have the following file upload handler:
public class FileUploader : IHttpHandler
{
public void ProcessRequest(HttpContext context)
{
HttpRequest request = context.Request;
context.Response.ContentType = "text/html";
context.Response.ContentEncoding = System.Text.Encoding.UTF8;
context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
var tempPath = request.PhysicalApplicationPath + "\\Files\\TempFiles\\";
byte[] buffer = new byte[request.ContentLength];
using (BinaryReader br = new BinaryReader(request.InputStream))
{
br.Read(buffer, 0, buffer.Length);
}
var tempName = WriteTempFile(buffer, tempPath);
context.Response.Write("{\"success\":true}");
context.Response.End();
}
public bool IsReusable
{
get { return true; }
}
private string WriteTempFile(byte[] buffer, string tempPath)
{
var fileName = GetUniqueFileName(tempPath);
File.WriteAllBytes(tempPath + fileName, buffer);
return fileName;
}
private string GetUniqueFileName(string tempPath)
{
var guid = Guid.NewGuid().ToString().ToUpper();
while (File.Exists(tempPath + guid))
{
guid = Guid.NewGuid().ToString().ToUpper();
}
return guid;
}
}
When I upload large files, this is causing OutOfMemoryException. Could someone tell what's right way to upload large files using such a handler?

There is no need to load a file into memory to write it to somewhere. You should be using a small buffer (maybe 8k), and looping over the streams. Or, with 4.0, the CopyTo method. For example:
using(var newFile = File.Create(tempPath)) {
request.InputStream.CopyTo(newFile);
}
(which does the small-buffer/loop for you, using a 4k buffer by default, or allowing a custom buffer-size to be passed via an overload)

You get an OutOfMemoryException because you load your uploaded file into memory.
Avoid this by writing your stream directly to a file.
public void ProcessRequest(HttpContext context)
{
const int BufferSize = 4096;
HttpRequest request = context.Request;
context.Response.ContentType = "text/html";
context.Response.ContentEncoding = System.Text.Encoding.UTF8;
context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
var tempFilePath = Path.GetTempFileName();
using (Stream fs = File.OpenWrite(tempFilePath));
{
byte[] buffer = new byte[BufferSize];
int read = -1;
while(read = request.InputStream.Read(buffer, 0, buffer.Length) > 0)
{
fs.Write(buffer, 0, buffer.Length);
}
}
context.Response.Write("{\"success\":true}");
context.Response.End();
}
edit: removed binaryreader