.net core unzip a file and zip subfolder

Question

I have a byte[] of a zip file. I need to unzip the file in memory and find "dist" folder inside the zip (there will be always a dist folder) and create a new zip file with whatever inside that "dist" folder.

"dist" folder could have files and sub-folders in it. I need the new zip file in byte[] so there will be in memory ONLY operation and no access to physical disk.

i try to use "SharpZipLib" no luck. i'm using .net core 2.0

Why don't you use the out-of-the-box framework-provided ZipArchive ? docs.microsoft.com/en-us/dotnet/api/… — Simon Mourier

Mohammad Khodabandeh Mohammad Khodabandeh · Accepted Answer · 2018-12-09T10:13:53

please try below code

   using (MemoryStream srcMemoryStream = new MemoryStream())
        {
            using (MemoryStream targetMemoryStream = new MemoryStream())
            {
                // to have a byte array, I just read a file and store it into a memory stream
                using (FileStream sourceZipFile = new FileStream(@"f:\source-file.zip", FileMode.Open))
                {
                    sourceZipFile.CopyTo(srcMemoryStream);
                }

                using (ZipArchive srcArchive = new ZipArchive(srcMemoryStream, ZipArchiveMode.Read))
                {
                    using (ZipArchive destArchive = new ZipArchive(targetMemoryStream, ZipArchiveMode.Create, true))
                    {

                        srcArchive.Entries
                            .Where(entry => entry.FullName.Contains("dist/"))
                            .ToList()
                            .ForEach((entry) =>
                            {
                                // i simply create the same folder with the same structure in other archive
                                // if you want to change the structure, you have to rename or remove parts of 
                                // the path like below
                                ///  var newEntryName = entry.FullName.Replace("files/dist/", "new-dist/");
                                ///  ZipArchiveEntry newEntry = destArchive.CreateEntry(newEntryName);
                                ZipArchiveEntry newEntry = destArchive.CreateEntry(entry.FullName);
                                using (Stream srcEntry = entry.Open())
                                {
                                    using (Stream destEntry = newEntry.Open())
                                    {
                                        srcEntry.CopyTo(destEntry);
                                    }
                                }
                            });
                    }
                }

                // i just write the zip file on disk to make sure that it works, your desire state is already achieved
                // before this line of code, and the result byte Array is inside the targetMemoryStream memory stream
                using (FileStream fs = new FileStream(@"f:/destination-file.zip", FileMode.Create))
                {
                    targetMemoryStream.WriteTo(fs);
                    targetMemoryStream.Flush();
                    fs.Flush(true);
                }

            }
        }

you can store those byte arrays in the memory stream, I just read a file and store it into a memory stream but you can simply use below code:

MemoryStream srcMemoryStream = new MemoryStream();
srcMemoryStream.Write(byteArray, 0, byteArray.Length);

.net core unzip a file and zip subfolder

1 Answers