ZipArchive Created with System.IO.Compression is Damaged

Question

I am having a hard time creating a ZipArchive successfully on Asp.net core MVC. I have an excel file generated with data that works and I need to put in an archive. This is what I've done so far

        public FileResult ExportGoodsReceiptData()
        {
            var records = _salesService.GetAllReceipts();
            var lineRecords = _salesService.GetAllReceiptLines();
            var result = _salesService.ExportGoodsReceiptData(records);
            var lineResult = _salesService.ExportGoodsReceiptLineData(lineRecords);

            byte[] resultArr = StreamToByteArray(result);
            byte[] lineResultArr = StreamToByteArray(lineResult);

            using(MemoryStream stream = new MemoryStream())
            {
                using (var archive = new ZipArchive(stream, ZipArchiveMode.Create, true))
                {
                    var zipArchiveEntry = archive.CreateEntry("GoodsReceipts.csv", CompressionLevel.Fastest);
                    using (var zipStream = zipArchiveEntry.Open())
                    using (var resultCom = new MemoryStream(resultArr))
                    {
                        resultCom.CopyTo(zipStream);
                    }
                }

                return new FileStreamResult(stream, "application/zip") { FileDownloadName = "GoodsReceiptsArchive.zip" };
            }
        }

When I run it, I get the zipfile, but can't open it. It throws error stating that it may have been damaged. I debugged the code to notice that one of the properties (length property) throws an invalidOperation exception. My approach looks identical to most samples I found online. Don't know how else to solve this. Please help.

Call .Dispose on your zipArchiveEntry variable to close the entry. — Jay Buckman, Sep 05 '17 at 15:02
@JayBuckman The Dispose() method does not exist in the object. — Kacey Ezerioha, Sep 05 '17 at 15:07
Here is an example https://stackoverflow.com/questions/29907291/downloading-of-zip-file-through-asp-net-mvc-using-dotnetzip Try removing the using from MemoryStream stream — WithMetta, Sep 05 '17 at 15:07
@WithMetta I already tried the approach of removing the using directive on memorystream and I got nothing. — Kacey Ezerioha, Sep 05 '17 at 15:12
You're disposing of the memory stream as you return it. The `FileStreamResult` effectively contains no data because the stream gets disposed. — , Sep 05 '17 at 15:25
@JayBuckman still didn't work. Although with the using directive, I don't think the Dispose() call is necessary — Kacey Ezerioha, Sep 05 '17 at 15:27
Yes. @KaceyEzerioha, you shouldn't edit in partial answers. Probably why your getting downvotes, it lets Amy's answer dangle in the air. I'll roll back. You can _add_ a section with a second version but that's not too important here. — H H, Sep 06 '17 at 08:38
I don't understand what you mean by editing partial answers. — Kacey Ezerioha, Sep 06 '17 at 08:45

score 0 · Answer 1 · answered Sep 05 '17 at 15:28

0

Your problem is that you're disposing of your memory stream before you return it. Remove this using:

using(MemoryStream stream = new MemoryStream())

Replace it with:

var stream = new MemoryStream();

Asp.Net MVC will automatically dispose of the stream for you.

answered Sep 05 '17 at 15:28

I tried it as someone suggested earlier but it still gave me a damaged zip file. – Kacey Ezerioha Sep 05 '17 at 15:31
Nevertheless, you do need to make this change. – Sep 05 '17 at 15:32
My current code has the change. I'm just yet to make the update on the question. – Kacey Ezerioha Sep 05 '17 at 15:35

ZipArchive Created with System.IO.Compression is Damaged

1 Answers1