I'm trying to output a CSV file to the client. When the save dialog comes up ( in both Internet Explorer 10 & Google Chrome ) and I try to open it from the browser, the file hangs and is stuck in "Running Security Scan". However, I am able to save the file without an problems. Below is the code I'm using to generate the file. Also to note, I have tried HttpContext.Current.Response.End(); and HttpContext.Current.ApplicationInstance.CompleteRequest(); and got the same result. Please help
string attachment = "attachment; filename=" + "MyCSVFile.csv";
var response = HttpContext.Current.Response;
response.Clear();
response.ClearHeaders();
response.ClearContent();
response.AddHeader("content-disposition", attachment);
response.ContentType = "text/csv";
var csv = new StringBuilder();
// ... Build contents for csv file
response.Write(csv.ToString());
response.End();
Apparently, the issue had nothing to do with my code but rather a corrupt file in Windows. I fixed this by opening command prompt with Run as Administrator and running the command sfc/scannow. It now downloads and opens correctly.
Related
I am working on an ASP.Net/VB.Net web application in which a file is to be generated and sent to the client when a button on the page is clicked. I have the following code to do this:-
Dim text_file_name As String = WriteOutputFile() ' Generate output file
Response.ClearContent()
Response.Clear()
Response.ContentType = "text/plain"
Response.AddHeader("Content-Disposition", "attachment; filename=" + text_file_name + ";")
Response.Flush()
HttpContext.Current.ApplicationInstance.CompleteRequest()
File.Delete(text_file_name)
This appears to complete and a file is duly downloaded, but on opening it I find it contains the web page HTML, rather than the intended file text. I observe though that the file (extension .csv) is opened up in Excel, so it is getting at least that part of the message.
I have verified that the file is created as intended by leaving out the File.Delete and watching the files accumulate in the server's directory.
In a previous attempt I had
Response.End()
in place of the complete request; this also generated a .csv file, but one containing the details of a thread exception.
Does anyone know what I am doing wrong?
You're sending the intended file name to the browser as a header hint but you aren't actually sending the file itself. To do that, use Response.WriteFile()
Currently I am generating an xml file for download using posted fields with the following code:
string attachment = "attachment; filename=" + FileName + ".xml";
Response.ClearContent();
Response.ContentType = "application/xml";
Response.AddHeader("content-disposition", attachment);
Response.Write(Session["FileForDownload"]);
Response.End();
This is working fine.
However I want to sftp upload the generated file to a specified directory on a server.
I have had success in connecting using ssh.net and have been able to create a new directory etc.
My question is how can I generate the file and then sftp it using ssh.net?
I've tried using a file stream with no success. I'm guessing the file needs to be temporarily stored and then retrieved for upload.
This is my current code segment for the specified problem:
SftpClient sftp = new SftpClient("host", "user", "pwd");
sftp.Connect();
sftp.ChangeDirectory("directory/");
Stream fs = File.OpenRead(Server.MapPath(#"filetobeuploaded"));
sftp.UploadFile(fs, Session["FileName"].ToString());
sftp.Disconnect();
I recognize that there won't be a file already on the server to upload.
Any help would be much appreciated as this is the final piece of the puzzle in my application.
Cheers
Fixed: I found a solution by generating a temp XML file in the server, uploading and deleting it. Thanks for your reply anyway
I have a website which allows secure (ssl) file uploads and download. The site runs on a Window 2003 server with IIS 6.0; asp.net 2.
When using this code:
protected void StartDownLoad(string filename)
{
Response.Clear();
if(filename.EndsWith("zip"))
Response.ContentType = "application/zip";
else
Response.ContentType = "application/msword";
string path = "C:\\Inetpub\\sites\\testsite\\secureDocs\\" + filename;
Response.WriteFile(path);
string headDesc = "inline;filename=" + filename;
Response.AddHeader("Content-Disposition", headDesc);
Response.End();
}
In my tests a 62MB file downloads without any problem -- a 65MB appear to start the download and then immediately stop. The http error logs have four entries each showing "Connection_Dropped". If I remove permissions from the folder and directly access the file through an https url I am able to download files that exceed 65MB so it doesn't seem like it's an IIS issue. Is there an asp.net setting that restricts the response write? Is it an IIS issue? Has anyone run into this before? Any solutions?
You can try using
Response.TransmitFile(path)
instead of
Response.WriteFile(path)
TransmitFile() doesn't buffer the file.
Bye.
After building a filepath (path, below) in a string (I am aware of Path in System.IO, but am using someone else's code and do not have the opportunity to refactor it to use Path). I am using a FileStream to deliver the file to the user (see below):
FileStream myStream = new FileStream(path, FileMode.Open, FileAccess.Read);
long fileSize = myStream.Length;
byte[] Buffer = new byte[(int)fileSize + 1];
myStream.Read(Buffer, 0, (int)myStream.Length);
myStream.Close();
Response.ContentType = "application/csv";
Response.AddHeader("content-disposition", "attachment; filename=" + filename);
Response.BinaryWrite(Buffer);
Response.Flush();
Response.End();
I have seen from: ASP.NET How To Stream File To User reasons to avoid use of Response.End() and Response.Close().
I have also seen several articles about different ways to transmit files and have diagnosed and found a solution to the problem (https and http headers) with a colleague.
However, the error message that was being displayed was not about access to the file at path, but the aspx file.
Edit: Error message is:
Internet Explorer cannot download MyPage.aspx from server.domain.tld
Internet Explorer was not able to open this Internet site. The requested site is either unavailable or cannot be found. Please try again later.
(page name and address anonymised)
Why is this? Is it due to the contents of the file coming from the HTTP response .Flush() method rather than a file being accessed at its address?
Even though you are sending a file, it is the "page" that contains the header information that describes the file you are sending. The browser still has to download that page, then sees the "attachment; filename=" and gives you the file instead.
So if there is an error, it will be page that is shown as the problem. It's a bit like getting a corrupted email with an attachment, you seen the problem in the email not the attachment itself.
Don't call Response.End();
What is the best way to implement, from a web page a download action using asp.net 2.0?
Log files for a action are created in a directory called [Application Root]/Logs. I have the full path and want to provide a button, that when clicked will download the log file from the IIS server to the users local pc.
Does this help:
http://www.west-wind.com/weblog/posts/76293.aspx
Response.ContentType = "application/octet-stream";
Response.AppendHeader("Content-Disposition","attachment; filename=logfile.txt");
Response.TransmitFile( Server.MapPath("~/logfile.txt") );
Response.End();
Response.TransmitFile is the accepted way of sending large files, instead of Response.WriteFile.
http://forums.asp.net/p/1481083/3457332.aspx
string filename = #"Specify the file path in the server over here....";
FileInfo fileInfo = new FileInfo(filename);
if (fileInfo.Exists)
{
Response.Clear();
Response.AddHeader("Content-Disposition", "attachment; filename=" + fileInfo.Name);
Response.AddHeader("Content-Length", fileInfo.Length.ToString());
Response.ContentType = "application/octet-stream";
Response.Flush();
Response.TransmitFile(fileInfo.FullName);
Response.End();
}
Update:
The initial code
Response.AddHeader("Content-Disposition", "inline;attachment; filename=" + fileInfo.Name);
has "inline;attachment" i.e. two values for Content Disposition.
Don't know when exactly it started, but in Firefox only the proper file name was not appearing. The file download box appears with the name of the webpage and its extension (pagename.aspx). After download, if you rename it back to the actual name; file opens successfully.
As per this page, it operates on First Come First Served basis. Changing the value to attachment only solved the issue.
PS: I am not sure if this is the best practice but the issue is resolved.