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Zip files created by DotNetZip using ASP.NET sometimes causing network error

I'm debugging a rather odd situation involving DotNetZip and ASP.NET. Long story short, the resulting zip files that are being created by the code are being reliably downloaded by Firefox, but most other browsers are intermittently returning a Network Error. I've examined the code and it reads about as generically as anything that involves DotNetZip.
Any clues?
Thanks!
EDIT: Here's the complete method. As I mentioned, it's about as generic as it gets:
protected void btnDownloadFolders_Click(object sender, EventArgs e)
{
//Current File path
var diRoot = new DirectoryInfo(_currentDirectoryPath);
var allFiles = Directory.GetFiles(diRoot.FullName, "*.*", SearchOption.AllDirectories);
Response.Clear();
Response.BufferOutput = false;
var archiveName = String.Format("{0}-{1}.zip", diRoot.Name, DateTime.Now.ToString("yyyy-MM-dd HHmmss"));
Response.ContentType = "application/zip";
Response.AddHeader("content-disposition", "inline; filename=\"" + archiveName + "\"");
using (var zip = new ZipFile())
{
foreach (var strFile in allFiles)
{
var strFileName = Path.GetFileName(strFile);
zip.AddFile(strFile,
strFile.Replace("\\" + strFileName, string.Empty).Replace(diRoot.FullName, string.Empty));
}
zip.Save(Response.OutputStream);
}
Response.Close();
}

It could be because you are not sending the content-length. I've seen errors occur in sending files to the browser where it was not specified. So create the zip file in a MemoryStream. save the stream to a Byte Array so you can send the length as a Response also. Although I can't say for sure that it will fix your specific problem.
byte[] bin;
using (MemoryStream ms = new MemoryStream())
{
using (var zip = new ZipFile())
{
foreach (var strFile in allFiles)
{
var strFileName = Path.GetFileName(strFile);
zip.AddFile(strFile, strFile.Replace("\\" + strFileName, string.Empty).Replace(diRoot.FullName, string.Empty));
}
//save the zip into the memorystream
zip.Save(ms);
}
//save the stream into the byte array
bin = ms.ToArray();
}
//clear the buffer stream
Response.ClearHeaders();
Response.Clear();
Response.Buffer = true;
//set the correct contenttype
Response.ContentType = "application/zip";
//set the filename for the zip file package
Response.AddHeader("content-disposition", "attachment; filename=\"" + archiveName + "\"");
//set the correct length of the data being send
Response.AddHeader("content-length", bin.Length.ToString());
//send the byte array to the browser
Response.OutputStream.Write(bin, 0, bin.Length);
//cleanup
Response.Flush();
HttpContext.Current.ApplicationInstance.CompleteRequest();

Error while reading and saving the excel file on serverside

I have tried the below coding for generating excel file on serverside.
C# CODING:
public void ReadandOpenExcel(DirectoryInfo outputDir)
{
//FileInfo newFile = new FileInfo(outputDir.FullName + #"\New Microsoft Excel Worksheet.xlsx");
var ExistFile = Server.MapPath("~/excelsample.xlsx");
var File = new FileInfo(ExistFile);
using (ExcelPackage package = new ExcelPackage(File))
{
package.Load(new FileStream(ExistFile, FileMode.Open));
ExcelWorksheet workSheet = package.Workbook.Worksheets["Sheet1"];
workSheet.Cells["A8"].Value = "kevin";
package.Save();
Response.Clear();
Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
Response.AddHeader("Content-Disposition", "attachment; filename=ProposalRequest.xslx");
**Response.BinaryWrite(package.GetAsByteArray());**
// myMemoryStream.WriteTo(Response.OutputStream); //works too
Response.Flush();
Response.Close();
}
}
While running the above code i got an error as : " Package object was closed and disposed, so cannot carry out operations on this object or any stream opened on a part of this package."
ERROR On This Line:
Response.BinaryWrite(package.GetAsByteArray());
Make some way for this coding to move on.
Thanks in advance.

Does it work if you get the bytes before you do the Save ?
Byte[] bin = package.GetAsByteArray();
package.Save();
And then use that value in the Binarywrite;
Response.BinaryWrite(bin);
Maybe it is getting closed on the .Save() call ?

C# return memory stream from OpenXML resulting to a corrupted word file

I have a problem with a MemoryStream from OpenXML. I succeed with opening a Word file, changing it and downloading it through the HttpResponse if I do all the steps in a single method.
But if I try to do it in two different classes (or methods) by returning the MemoryStream, I get a corrupted word file. I thought about a flushing or buffer problem but I don't find a solution.
Here is the working code :
public void FillTemplateOpenXmlWord(HttpResponse response)
{
string filePath = #"c:\template.docx";
byte[] filebytes = File.ReadAllBytes(filePath);
using (MemoryStream stream = new MemoryStream(filebytes))
{
using (WordprocessingDocument myDoc = WordprocessingDocument.Open(stream, true))
{
// do some changes
...
myDoc.MainDocumentPart.Document.Save();
}
string docx = "docx";
response.Clear();
response.ClearHeaders();
response.ClearContent();
response.AddHeader("content-disposition", "attachment; filename=\"" + docx + ".docx\"");
response.ContentType = "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
response.ContentEncoding = Encoding.GetEncoding("ISO-8859-1");
stream.Position = 0;
stream.CopyTo(response.OutputStream);
response.End();
}
}
Here is the non-working code :
public void OpenFile(HttpResponse response)
{
MemoryStream stream = this.FillTemplateOpenXmlWord();
string docx = "docx";
response.Clear();
response.ClearHeaders();
response.ClearContent();
response.AddHeader("content-disposition", "attachment; filename=\"" + docx + ".docx\"");
response.ContentType = "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
response.ContentEncoding = Encoding.GetEncoding("ISO-8859-1");
stream.Position = 0;
stream.CopyTo(response.OutputStream);
response.End();
}
public MemoryStream FillTemplateOpenXmlWord()
{
string filePath = #"c:\template.docx";
byte[] filebytes = File.ReadAllBytes(filePath);
using (MemoryStream stream = new MemoryStream(filebytes))
{
using (WordprocessingDocument myDoc = WordprocessingDocument.Open(stream, true))
{
// do some changes
...
myDoc.MainDocumentPart.Document.Save();
}
return stream;
}
}
Any idea ?
thank you

Here's what I'm using for generating OpenXML files from memory stream. In this case it makes XLSX file from template on server, but it should be similar for other OpenXml formats.
Controller action:
public class ExportController : Controller
{
public FileResult Project(int id)
{
var model = SomeDateModel.Load(id);
ProjectExport export = new ProjectExport();
var excelBytes = export.Export(model);
FileResult fr = new FileContentResult(excelBytes, "application/vnd.ms-excel")
{
FileDownloadName = string.Format("Export_{0}_{1}.xlsx", DateTime.Now.ToString("yyMMdd"), model.Name)
};
return fr;
}
}
// Helper class
public class ProjectExport
{
private WorkbookPart workbook;
private Worksheet ws;
public byte[] Export(SomeDateModel model)
{
var template = new FileInfo(HostingEnvironment.MapPath(#"~\Export\myTemplate.xlsx"));
byte[] templateBytes = File.ReadAllBytes(template.FullName);
using (var templateStream = new MemoryStream())
{
templateStream.Write(templateBytes, 0, templateBytes.Length);
using (var excelDoc = SpreadsheetDocument.Open(templateStream, true))
{
workbook = excelDoc.WorkbookPart;
var sheet = workbook.Workbook.Descendants<Sheet>().First();
ws = ((WorksheetPart)workbook.GetPartById(sheet.Id)).Worksheet;
sheet.Name = model.Name;
// Here write some other stuff for setting values in cells etc...
}
templateStream.Position = 0;
var result = templateStream.ToArray();
templateStream.Flush();
return result;
}
}

looks like stream is closing when you return. it is in a using block. wouldn't that close the memory stream as soon as the filltemplate procedure ends?

The answer posted by gashac does not describe the issues you are going to get by not calling dispose on a stream.
Not disposing a memory stream causes memory leaks (same as a "using clause").
Memory streams keeps data in memory whereas file streams keeps data on the hdd.
Solution:
Save the memory stream into a byte array, dispose the memory stream and return the bytearray.
How to return bytearray instead stream
See the following thread to return a file as a bytearray:
HttpResponseMessage Content won't display PDF

TransmitFile and WriteFile

I use TransmitFile and WriteFile to write an Excel File, but anyone does not work correctly
my code is :
// Get the Physical Path of the file(test.doc)
string filepath = newFilePath;
// Create New instance of FileInfo class to get the properties of the file being downloaded
FileInfo file = new FileInfo(filepath);
// Checking if file exists
if (file.Exists)
{
// Clear the content of the response
HttpContext.Current.Response.ClearContent();
// LINE1: Add the file name and attachment, which will force the open/cance/save dialog to show, to the header
HttpContext.Current.Response.AddHeader("Content-Disposition", String.Format("attachment; filename={0}", file.Name));
// Add the file size into the response header
HttpContext.Current.Response.AddHeader("Content-Length", file.Length.ToString());
// Set the ContentType
HttpContext.Current.Response.ContentType = "application/vnd.ms-excel";
// Write the file into the response (TransmitFile is for ASP.NET 2.0. In ASP.NET 1.1 you have to use WriteFile instead)
HttpContext.Current.Response.TransmitFile(file.FullName);
}
FileStream sourceFile = new FileStream(file.FullName, FileMode.Open);
float FileSize;
FileSize = sourceFile.Length;
byte[] getContent = new byte[(int)FileSize];
sourceFile.Read(getContent, 0, (int)sourceFile.Length);
sourceFile.Close();
HttpContext.Current.Response.ClearContent();
HttpContext.Current.Response.ClearHeaders();
HttpContext.Current.Response.Buffer = true;
HttpContext.Current.Response.ContentType = "application/vnd.ms-excel";
HttpContext.Current.Response.AddHeader("Content-Length", getContent.Length.ToString());
HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=" + fileName);
HttpContext.Current.Response.BinaryWrite(getContent);

I would simplify it to this instead:
public ActionResult ExcelDoc(string newFilePath)
{
string filepath = newFilePath;
// Create New instance of FileInfo class to get the properties of the file being downloaded
FileInfo file = new FileInfo(filepath);
// Checking if file exists
if (file.Exists)
{
var fileBytes = System.IO.File.ReadAllBytes(filepath);
Response.AddHeader("Content-Disposition", String.Format("attachment; filename={0}", file.Name));
return File(new MemoryStream(fileBytes), "application/vnd.ms-excel");
}
else
{
return Content("File does not exist");
}
}

Generating an excel file with EPPlus is failing

When I try to generate an Excel file using EPPlus, Excel give me the following error message:
Excel cannot open the file 'myfilename.xlsx' because the file format or file extension is not valid. Verify the the file has not been corrupted and that the file extension matches the format of the file.
Here's my code:
public ActionResult Index()
{
using (ExcelPackage package = new ExcelPackage())
{
// I populate the worksheet here. I'm 90% sure this is fine
// because the stream file size changes based on what I pass to it.
var stream = new MemoryStream();
package.SaveAs(stream);
string fileName = "myfilename.xlsx";
string contentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
var cd = new System.Net.Mime.ContentDisposition
{
Inline = false,
FileName = fileName
};
Response.AppendHeader("Content-Disposition", cd.ToString());
return File(stream, contentType, fileName);
}
}
Any idea what I'm doing wrong?

All you need to do is reset the stream position. stream.Position = 0;
You shouldn't write directly to the Response, it's not the MVC way. It doesn't follow the correct MVC pipeline and it tightly couples your controller action code to the Response object.
When you add a file name as the 3rd parameter in File(), MVC automatically adds the correct Content-Disposition header... so you shouldn't need to add it manually.
The short of it is, this is what you want:
public ActionResult Index()
{
using (ExcelPackage package = new ExcelPackage())
{
// I populate the worksheet here. I'm 90% sure this is fine
// because the stream file size changes based on what I pass to it.
var stream = new MemoryStream();
package.SaveAs(stream);
string fileName = "myfilename.xlsx";
string contentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
stream.Position = 0;
return File(stream, contentType, fileName);
}
}

Your code doesn't show stream being written to the HttpResponse - presumably being done in the File method which you haven't posted.
One way that does work is the following:
Response.Clear();
Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
Response.AddHeader(
"content-disposition", String.Format(CultureInfo.InvariantCulture, "attachment; filename={0}", fileName));
Response.BinaryWrite(package.GetAsByteArray());
Response.End();

Similar to Joe's answer, I still had to call Response.ClearHeaders():
protected void btnDownload_Click(object sender, EventArgs e)
{
ExcelPackage pck = new ExcelPackage();
var ws = pck.Workbook.Worksheets.Add("Sample2");
ws.Cells["A1"].Value = "Sample 2";
ws.Cells["A1"].Style.Font.Bold = true;
var shape = ws.Drawings.AddShape("Shape1", eShapeStyle.Rect);
shape.SetPosition(50, 200);
shape.SetSize(200, 100);
shape.Text = "Sample 2 outputs the sheet using the Response.BinaryWrite method";
Response.Clear();
Response.ClearHeaders();
Response.BinaryWrite(pck.GetAsByteArray());
Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
Response.AddHeader("content-disposition", "attachment; filename=Sample2.xlsx");
Response.End();
}