使用C＃将文件和文件夹下载为ZIP文件在Mac中不起作用

Question

I'm using the following code to download a set of files and folders as a ZIP, which works great in a Windows, but not in a Mac

string SourceFolderPath = System.IO.Path.Combine(FolderPath, "Initial"); 
string SourceZip = System.IO.Path.Combine(UserTemp, nameFolder + ".zip");

            if (Directory.Exists(SourceFolderPath))
            {
                if (File.Exists(SourceZip)) { File.Delete(SourceZip); }
                ZipInfo zip = new ZipInfo(SourceZip);
                zip.Pack(SourceFolderPath, true, CompressionLevel.None, null);

                if (File.Exists(SourceZip))
                {
                    System.IO.FileInfo file = new System.IO.FileInfo(SourceZip);
                    Response.ClearContent();
                    Response.AddHeader("Content-Disposition", String.Format("attachment; filename={0}", file.Name));
                    Response.AddHeader("Content-Length", file.Length.ToString());
                    Response.ContentType = "application/zip";
                    this.EnableViewState = false;
                    Response.TransmitFile(file.FullName);
                    Response.Flush();
                    File.Delete(SourceZip);
                    Response.End();
                }
            }

When using a Mac, inside of the resultant ZIP the folders disappear, and the files which should be in folders are called like images\\picture1.png

I'm using Path.Combine to get the folder's path, could be because of that?

string SourceFolderPath = System.IO.Path.Combine(FolderPath, "Initial"); 
string SourceZip = System.IO.Path.Combine(UserTemp, nameFolder + ".zip");

Any advice would be great. :)

Answer 1

If you're using .NET Framework 4.5 or newer you can do this using the highly-efficient ASP.NET native System.IO.Compression.ZipArchive class, which should be fully compatible with any zip implementation you can find (Windows OS, MAC OS and so on).

Here's a quick implementation sample using a MemoryStream and a couple of byte arrays representing two files:

byte[] file1 = GetFile1ByteArray();
byte[] file2 = GetFile2ByteArray();

using (MemoryStream ms = new MemoryStream())
{
    using (var archive = new ZipArchive(ms, ZipArchiveMode.Create, true))
    {
        var zipArchiveEntry = archive.CreateEntry("file1.txt", CompressionLevel.Fastest);
        using (var zipStream = zipArchiveEntry.Open()) zipStream.Write(file1, 0, file1.Length);
        zipArchiveEntry = archive.CreateEntry("file2.txt", CompressionLevel.Fastest);
        using (var zipStream = zipArchiveEntry.Open()) zipStream.Write(file2, 0, file2.Length);
    }
    return File(ms.ToArray(), "application/zip", "Archive.zip");
}

Depending on your scenario you can use it inside a MVC Controller returning an ActionResult , persist the MemoryStream to disk, replace it with a FileStream and so on: in the above example I used the Controller.File method (from System.Web.Mvc namespace) to return a FileContentResult object. If you're not using the MVC Framework you cannot do that, but you can still handle the MemoryStream in a different way - by using Response.OutputStream or other standard techniques.

For further info regarding this topic you can also read this post on my blog.

Answer 2

I ended up using DotNetZip to create the zip file. Here is the code I used

    string SourceFolderPath = System.IO.Path.Combine(FolderPath, "Initial");

    Response.Clear();
    Response.ContentType = "application/zip";
    Response.AddHeader("Content-Disposition", String.Format("attachment; filename={0}", nameFolder + ".zip"));

    bool recurseDirectories = true;
    using (ZipFile zip = new ZipFile())
    {
        zip.AddSelectedFiles("*", SourceFolderPath, string.Empty, recurseDirectories);
        zip.Save(Response.OutputStream);
    }
    Response.End();

No problem extracting the content from zip using a Mac.