I am trying to programatically download a file through clicking a link, on my site (it's a .doc file sitting on my web server). This is my code:
string File = Server.MapPath(#"filename.doc");
string FileName = "filename.doc";
if (System.IO.File.Exists(FileName))
{
FileInfo fileInfo = new FileInfo(File);
long Length = fileInfo.Length;
Response.ContentType = "Application/msword";
Response.AddHeader("Content-Disposition", "attachment; filename=" + fileInfo.Name);
Response.AddHeader("Content-Length", Length.ToString());
Response.WriteFile(fileInfo.FullName);
}
This is in a buttonclick event handler. Ok I could do something about the file path/file name code to make it neater, but when clicking the button, the page refreshes. On localhost, this code works fine and allows me to download the file ok. What am I doing wrong?
Thanks
Rather than having a button click event handler you could have a download.aspx page that you could link to instead.
This page could then have your code in the page load event. Also add Response.Clear(); before your Response.ContentType = "Application/msword"; line and also add Response.End(); after your Response.WriteFile(fileInfo.FullName); line.
Try a slightly modified version:
string File = Server.MapPath(#"filename.doc");
string FileName = "filename.doc";
if (System.IO.File.Exists(FileName))
{
FileInfo fileInfo = new FileInfo(File);
Response.Clear();
Response.ContentType = "Application/msword";
Response.AddHeader("Content-Disposition", "attachment; filename=" + fileInfo.Name);
Response.WriteFile(fileInfo.FullName);
Response.End();
}
Oh, you shouldn't do it in button click event handler. I suggest moving the whole thing to an HTTP Handler (.ashx) and use Response.Redirect or any other redirection method to take the user to that page. My answer to this question provides a sample.
If you still want to do it in the event handler. Make sure you do a Response.End call after writing out the file.
Related
I want to make the browser download a PDF document from server instead of opening the file in browser itself. I am using C#.
Below is my sample code which I used. It not working..
string filename = "Sample server url";
response.redirect(filename);
You should look at the "Content-Disposition" header; for example setting "Content-Disposition" to "attachment; filename=foo.pdf" will prompt the user (typically) with a "Save as: foo.pdf" dialog, rather than opening it. This, however, needs to come from the request that is doing the download, so you can't do this during a redirect. However, ASP.NET offers Response.TransmitFile for this purpose. For example (assuming you aren't using MVC, which has other preferred options):
Response.Clear();
Response.ContentType = "application/pdf";
Response.AppendHeader("Content-Disposition", "attachment; filename=foo.pdf");
Response.TransmitFile(filePath);
Response.End();
If you want to render the file(s) so that you could save them at your end instead of opening in the browser, you may try the following code snippet:
//create new MemoryStream object and add PDF file’s content to outStream.
MemoryStream outStream = new MemoryStream();
//specify the duration of time before a page cached on a browser expires
Response.Expires = 0;
//specify the property to buffer the output page
Response.Buffer = true;
//erase any buffered HTML output
Response.ClearContent();
//add a new HTML header and value to the Response sent to the client
Response.AddHeader(“content-disposition”, “inline; filename=” + “output.pdf”);
//specify the HTTP content type for Response as Pdf
Response.ContentType = “application/pdf”;
//write specified information of current HTTP output to Byte array
Response.BinaryWrite(outStream.ToArray());
//close the output stream
outStream.Close();
//end the processing of the current page to ensure that no other HTML content is sent
Response.End();
However, if you want to download the file using a client application then you'll have to use the WebClient class.
I use this by setting inline parameter to true it will show in browser false it will show save as dialog in browser.
public void ExportReport(XtraReport report, string fileName, string fileType, bool inline)
{
MemoryStream stream = new MemoryStream();
Response.Clear();
if (fileType == "xls")
report.ExportToXls(stream);
if (fileType == "pdf")
report.ExportToPdf(stream);
if (fileType == "rtf")
report.ExportToRtf(stream);
if (fileType == "csv")
report.ExportToCsv(stream);
Response.ContentType = "application/" + fileType;
Response.AddHeader("Accept-Header", stream.Length.ToString());
Response.AddHeader("Content-Disposition", String.Format("{0}; filename={1}.{2}", (inline ? "Inline" : "Attachment"), fileName, fileType));
Response.AddHeader("Content-Length", stream.Length.ToString());
//Response.ContentEncoding = System.Text.Encoding.Default;
Response.BinaryWrite(stream.ToArray());
Response.End();
}
In case if we are trying to write a bytes array then we can use below one.
Response.Clear();
Response.ContentType = "application/pdf";
Response.AppendHeader("Content-Disposition", "attachment; filename=file.pdf");
Response.BufferOutput = true;
Response.AddHeader("Content-Length", docBytes.Length.ToString());
Response.BinaryWrite(docBytes);
Response.End();
They are almost same in most of the cases but there is a difference:
Add Header will replace the previous entry with the same key
Append header will not replace the key, rather will add another one.
i am using the following code to open the pdf byte[] file without saving it. It is working fine but after this action no other server side actions like button click are not working. Postback is not working.
byte[] bytfile = Objects.GetFile(Convert.ToInt32(txtslno.Text.Trim()));
Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.ContentType = "application/pdf";
Response.AddHeader("Content-Disposition", "attachment;filename="+filename);
Response.AddHeader("Content-Length", bytfile.Length.ToString());
Response.OutputStream.Write(bytfile, 0, bytfile.Length);
Response.Flush();
Response.End();
Try this. It shoulld work.
byte[] bytfile = Objects.GetFile(Convert.ToInt32(txtslno.Text.Trim()));
Response.Clear();
MemoryStream ms = new MemoryStream(bytfile);
Response.ContentType = "application/pdf";
Response.AddHeader("content-disposition", "attachment;filename=test.pdf");
Response.Buffer = true;
ms.WriteTo(Response.OutputStream);
Response.End();
else try
Response.BinaryWrite(bytfile);
instead of
ms.WriteTo(Response.OutputStream);
in above code.
It is working fine but after this action no other server side actions
like button click are not working.
Are you using your code inside a page or a control?
Use a generic handler (*.ashx) for your purpose. The code for downloading the pdf won't cause troubles for the application anymore.
https://stackoverflow.com/a/12340735/225808 might be useful as a reference.
In ASP.Net (with C#) I'm trying to create a .DAT file with plain text in it and send it to the browser and force download. I've tried several things but I can't get it working. In my aspx-file there is an ImageButton
<asp:ImageButton ID="btnSave" runat="server" CausesValidation="False" ImageUrl="~/Images/Stages/Database/Save.png" OnClick="btnSave_OnClick" Width="26px" />
In the OnClick-method I'm trying to create the file and send it to the browser.
protected void btnSave_OnClick(object sender, EventArgs e)
{
string file = "test.dat";
string fileName = "~\\Stages\\Broekx\\Databanken\\" + file;
FileStream fs = new FileStream(MapPath(fileName), FileMode.Open);
long cntBytes = new FileInfo(MapPath(fileName)).Length;
byte[] byteArray = new byte[Convert.ToInt32(cntBytes)];
fs.Read(byteArray, 0, Convert.ToInt32(cntBytes));
fs.Close();
ImageButton btnSave = (ImageButton)FormViewStagesDummy.FindControl("btnSave");
btnSave.Visible = false;
File.Delete(Server.MapPath(fileName));
if (byteArray != null)
{
this.Response.Clear();
this.Response.ContentType = "text/plain";
this.Response.AddHeader("content-disposition", "attachment;filename=" + file);
this.Response.BinaryWrite(byteArray);
this.Response.End();
this.Response.Flush();
this.Response.Close();
}
}
The file test.dat exists in the correct folder and has to be deleted after it has been read into bytes. I've tried this without deleting the file and that wont work either.
After clicking btnSave the button has to be hidden, so that's why I set the parameter Visible to false.
I've also tried it with content-type "application/octet-stream" or with a PDF file and content-type "application/pdf" but nothing works. The page loads normally and no file is being downloaded.
Is the file string's path actually correct?
this.Response.AddHeader("content-disposition", "attachment;filename=" + file);
Should it not be filename?
Why are you deleting the file before it is written to the response? Would it not make more sense to serve the file via the response and then delete it?
i.e. call
File.Delete(Server.MapPath(fileName));
after the repsonse.
You should try:
Response.TransmitFile( Server.MapPath(fileName) );
Response.End();
TransmitFile is very efficient because it basically offloads the file streaming to IIS including potentially causing the file to get cached in the Kernal cache (based on IIS's caching rules).
Response.End();
Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.ContentType = "text/plain";
Response.AppendHeader("Content-Disposition", "attachment; filename = " + fileName);
Response.TransmitFile(Server.MapPath("~/foldername/" + fileName));
Response.End();
I try to load a small pdf file to client browser. I redirect to download_page.aspx that does the following:
Response.ClearHeaders();
Response.ContentType = "application/pdf";
Response.Clear();
Response.AppendHeader("Content-Disposition", "attachment");
Response.TransmitFile(file);
Response.Flush();
Problem:
When I redirect to download_page.aspx from a link or from a button.OnClientClick="javascript:window.open('download_page.aspx?index=20')"
it works. PDF opens in client browser.
However, when I click on a button that does something on the page and then i use ClientScript.RegisterStartupScript to redirect to download_page.aspx, then download_page.aspx just blinks (flashes) and closes, no pdf loaded.
This is IE7, IE8 problem. It works in Firefox.
Any help appreciated.
Thank you,
Raman.
First of all, you don't need to ClearHeaders Clear and Flush, so your code should look like:
Response.ContentType = "application/pdf";
Response.AppendHeader("Content-Disposition", "attachment");
Response.TransmitFile(file);
Now, you should also improve the Content-Disposition header value and add the file name to ease end-users browser experience. IE is different than other with regards with how the file name can be encoded in case it has special characters, so here is a sample code that you might use or change to your will:
public static void AddContentDispositionHeader(HttpResponse response, string disposition, string fileName)
{
if (response == null)
throw new ArgumentNullException("response");
StringBuilder sb = new StringBuilder(disposition + "; filename=\"");
string text;
if ((HttpContext.Current != null) && (string.Compare(HttpContext.Current.Request.Browser.Browser, "IE", StringComparison.OrdinalIgnoreCase) == 0))
{
text = HttpUtility.UrlPathEncode(fileName);
}
else
{
text = fileName;
}
sb.Append(text);
sb.Append("\"");
response.AddHeader("Content-Disposition", sb.ToString());
}
Now, your code can be written as:
Response.ContentType = "application/pdf";
AddContentDispositionHeader(Response, "attachment", filename);
Response.TransmitFile(file);
The last thing is: make sure nobody deletes the files or writes to it during its transmission.
I met the same condition as yours.
I finally solved it.
Don't use window.open. You can simply use
window.location = 'download_page.aspx?index=20'
Note that the original page will remain well.
Reference from here and from here
What i want to do is that the user selects some fields on a grid and according to these datas i create an xml file on the web server and then i want user to download it like downloading a any file. But the problem is, i cant use this code:
Response.ContentType = "APPLICATION/OCTET-STREAM";
// initialize the http content-disposition header to
// indicate a file attachment with the default filename
// "myFile.txt"
System.String disHeader = "Attachment; Filename=\"" + fileName +
"\"";
Response.AppendHeader("Content-Disposition", disHeader);
FileInfo downloadFile = new FileInfo(fileFullName);
if (downloadFile.Exists)
{
Response.WriteFile(downloadFile.FullName);
HttpContext.Current.ApplicationInstance.CompleteRequest();
}
Because i need to let the user download 3 files so the header cannot cary it, what i tought was getting the file names and open a popup, list the file names with a linkbutton, and then the user can download it.
For each file i create a linkbutton at runtime and add this code :
lnkProblem.Text = "Problemler dosyası";
lnkProblem.Visible = true;
lnkProblem.Command += new CommandEventHandler(lnkUser_Command);
lnkProblem.CommandName = Request.QueryString["fileNameProblems"];
lnkProblem.CommandArgument = Request.QueryString["fileNameProblems"];
Then use this function to make it download by the user :
void lnkUser_Command(object sender, CommandEventArgs e)
{
Response.ContentType = "APPLICATION/XML";
System.String disHeader = "Attachment; Filename=\"" + e.CommandArgument.ToString() +
"\"";
Response.AppendHeader("Content-Disposition", disHeader);
FileInfo downloadFile = new FileInfo(Server.MapPath(".") + "\\xmls\\" + e.CommandArgument.ToString());
if (downloadFile.Exists)
{
Response.WriteFile(Server.MapPath(".") + "\\xmls\\" + e.CommandArgument.ToString());
HttpContext.Current.ApplicationInstance.CompleteRequest();
}
HttpContext.Current.ApplicationInstance.CompleteRequest();
}
Application creates the xml file but somewhere of it, app puts the html tags in that xml file so i can't open the file, is there anyway to do this? Maybe any other example...
The cleaneast way to send a file to the client is to use the TransmitFile method like this:
FileInfo file = new FileInfo(filePath); // full file path on disk
Response.ClearContent(); // neded to clear previous (if any) written content
Response.AddHeader("Content-Disposition",
"attachment; filename=" + file.Name);
Response.AddHeader("Content-Length", file.Length.ToString());
Response.ContentType = "text/xml"; //RFC 3023
Response.TransmitFile(file.FullName);
Response.End();
For multiple files a common solution is to pack all files in a zip file and send them (the mime type would be application/zip in this case).
Create a separate IHttpHandler which would only serve files you want your users to download, and Redirect to that handler in lnkUser_Command.