Pdfs inside zip file are corrupted

Question

I am trying to make a zip file that contains pdfs. When i extract the zip, the pdfs are corrupted. I placed a watch on 'outputStream'. Here is the first exception

'outputStream.Length' threw an exception of type 'System.NotSupportedException' long

here is the entire watch watch

Code

[HttpPost]
    [ActionName("ZipFileAction")]
    public HttpResponseMessage ZipFiles([FromBody]int[] id)
    {
        if (id == null)
        {//Required IDs were not provided
            throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.BadRequest));
        }

        List<Document> documents = new List<Document>();
        using (var context = new ApplicationDbContext())
        {
            foreach (int NextDocument in id)
            {
                Document document = context.Documents.Find(NextDocument);

                if (document == null)
                {
                    throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.NotFound));
                }

                documents.Add(document);
            }
            var streamContent = new PushStreamContent((outputStream, httpContext, transportContent) =>
            {
                try
                {
                    using (var zipFile = new ZipFile())
                    {
                        foreach (var d in documents)
                        {
                            var dt = d.DocumentDate.ToString("y").Replace('/', '-').Replace(':', '-');
                            string fileName = String.Format("{0}-{1}-{2}.pdf", dt, d.PipeName, d.LocationAb);
                            zipFile.AddEntry(fileName, d.DocumentUrl);
                        }
                        zipFile.Save(outputStream); //Null Reference Exception
                    }
                }

                finally
                {
                    outputStream.Close();
                }
            });
            streamContent.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
            streamContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
            streamContent.Headers.ContentDisposition.FileName = "reports.zip";

            var response = new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = streamContent
            };
            return response;
        }

David S. · Answer 1 · 2015-05-14T22:34:37.000

1

PushStreamContent is for data streaming. I think you should create a temporary zip file, and pass it to the Response.

Example

public FileResult ZipFiles(...)
{
   // create a temporary file

    return File("path/to/file.zip", System.Net.Mime.MediaTypeNames.Application.Octet);
}

edited May 14 '15 at 22:34

answered May 14 '15 at 11:14

David S.

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Please see the example. Also, the answer to [this](https://stackoverflow.com/questions/3604562/download-file-of-any-type-in-asp-net-mvc-using-fileresult) post is pretty good as well. – David S. May 14 '15 at 22:35

score 1 · Accepted Answer · answered May 16 '15 at 03:58

problem turned out to be i was not saving any content in the pdf. I was just saving the documentUrl. so changed things up by using FileInfo to do that. working code

[HttpPost]
    [ActionName("ZipFileAction")]
    public HttpResponseMessage ZipFiles([FromBody]int[] id)
    {
        if (id == null)
        {//Required IDs were not provided
            throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.BadRequest));
        }

        List<Document> documents = new List<Document>();
        using (var context = new ApplicationDbContext())
        {
            foreach (int NextDocument in id)
            {
                Document document = context.Documents.Find(NextDocument);

                if (document == null)
                {
                    throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.NotFound));
                }

                documents.Add(document);
            }
            var streamContent = new PushStreamContent((outputStream, httpContext, transportContent) =>
            {
                try
                {
                    using (var zipFile = new ZipFile())
                    {
                        foreach (var d in documents)
                        {
                            var dt = d.DocumentDate.ToString("y").Replace('/', '-').Replace(':', '-');
                            string fileName = String.Format("{0}-{1}-{2}.pdf", dt, d.PipeName, d.LocationAb);
                            FileInfo fi = new FileInfo(d.DocumentUrl);
                            var fileReadStream = fi.OpenRead();
                            var fileSize = (int)fi.Length;
                            var fileContent = new byte[fileSize];
                            fileReadStream.Read(fileContent, 0, fileSize);
                            zipFile.AddEntry(fileName, fileContent);
                        }
                        zipFile.Save(outputStream); //Null Reference Exception
                    }
                }

                finally
                {
                    outputStream.Close();
                }
            });
            streamContent.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
            streamContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
            streamContent.Headers.ContentDisposition.FileName = "reports.zip";

            var response = new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = streamContent
            };
            return response;
        }
    }
}

Pdfs inside zip file are corrupted

2 Answers2

Example