DotNetZip Saving to Stream

Question

I am using DotNetZip to add a file from a MemoryStream to a zip file and then to save that zip as a MemoryStream so that I can email it as an attachment. The code below does not err but the MemoryStream must not be done right because it is unreadable. When I save the zip to my hard drive everything works perfect, just not when I try to save it to a stream.

using (ZipFile zip = new ZipFile())
{
var memStream = new MemoryStream();
var streamWriter = new StreamWriter(memStream);

streamWriter.WriteLine(stringContent);

streamWriter.Flush();      
memStream.Seek(0, SeekOrigin.Begin);

ZipEntry e = zip.AddEntry("test.txt", memStream);
e.Password = "123456!";
e.Encryption = EncryptionAlgorithm.WinZipAes256;

var ms = new MemoryStream();
ms.Seek(0, SeekOrigin.Begin);

zip.Save(ms);

//ms is what I want to use to send as an attachment in an email                                   
}

Solution 1

I've copied your code, and then saved your final memory steam to disk as data.txt. It was completely unreadable to me, but then I realized that it wasn't a text file, it was a zip file, so i saved it as data.zip and it worked as expected

the method I used to save ms to disk is the following(immediately after your zip.Save(ms); line)

            ms.Position = 0;
            byte[] data = ms.ToArray();
            File.WriteAllBytes("data.zip", data);

So, I believe that your memory stream is what It is supposed to be, which is compressed text. It won't be readable until you decompress it.

Solution 2

Ok, I figured out my problem, pretty stupid actually. Thanks for everyone's help!

ZipEntry e = zip.AddEntry("test.txt", memStream);
e.Password = "123456!";
e.Encryption = EncryptionAlgorithm.WinZipAes256;

//zip.Save("C:\\Test\\Test.zip");

//Stream outStream;

var ms = new MemoryStream();

zip.Save(ms);

    //--Needed to add the following 2 lines to make it work----
ms.Seek(0, SeekOrigin.Begin);
ms.Flush();

Comments

[user229133]

When I get the memory stream named "ms" to disk and try to unzip it I get the error "The archive is either in unknown format or damaged". Are you talking about the memory stream "ms" or "memStream"?

[Sam I am says Reinstate Monica]

@user229133 I've just edited my post to show you how I saved ms to disk. Try that

[SerG]

Instead of last two lines a Using-statment should be used over ms.