Chapter 100: Reading and writing .zip files

Parameter Details

archiveFileName The path to the archive to open, specified as a relative or absolute path. A relative path is interpreted as relative to the current working directory.

Section 100.1: Writing to a zip file

To write a new .zip file:

System.IO.Compression

System.IO.Compression.FileSystem

using (FileStream zipToOpen = new FileStream(@"C:\temp", FileMode.Open))

{

using (ZipArchive archive = new ZipArchive(zipToOpen, ZipArchiveMode.Update))

{

ZipArchiveEntry readmeEntry = archive.CreateEntry("Readme.txt"); using (StreamWriter writer = new StreamWriter(readmeEntry.Open()))

{

writer.WriteLine("Information about this package."); writer.WriteLine("========================");

}

}

}

Section 100.2: Writing Zip Files in-memory

The following example will return the byte[] data of a zipped file containing the files provided to it, without needing access to the file system.

public static byte[] ZipFiles(Dictionary<string, byte[]> files)

{

using (MemoryStream ms = new MemoryStream())

{

using (ZipArchive archive = new ZipArchive(ms, ZipArchiveMode.Update))

{

foreach (var file in files)

{

ZipArchiveEntry orderEntry = archive.CreateEntry(file.Key); //create a file with

using (BinaryWriter writer = new BinaryWriter(orderEntry.Open()))

{

writer.Write(file.Value); //write the binary data

}

}

}

//ZipArchive must be disposed before the MemoryStream has data return ms.ToArray();

}

}

Section 100.3: Get files from a Zip file

This example gets a listing of files from the provided zip archive binary data:

public static Dictionary<string, byte[]> GetFiles(byte[] zippedFile)

{

using (MemoryStream ms = new MemoryStream(zippedFile))

using (ZipArchive archive = new ZipArchive(ms, ZipArchiveMode.Read))

{

return archive.Entries.ToDictionary(x => x.FullName, x => ReadStream(x.Open()));

}

}

private static byte[] ReadStream(Stream stream)

{

using (var ms = new MemoryStream())

{

stream.CopyTo(ms); return ms.ToArray();

}

}

Section 100.4: The following example shows how to open a zip archive and extract all .txt files to a folder

using System; using System.IO;

using System.IO.Compression;

namespace ConsoleApplication1

{

class Program

{

static void Main(string[] args)

{

string zipPath = @"c:\example\start.zip"; string extractPath = @"c:\example\extract";

using (ZipArchive archive = ZipFile.OpenRead(zipPath))

{

foreach (ZipArchiveEntry entry in archive.Entries)

{

if (entry.FullName.EndsWith(".txt", StringComparison.OrdinalIgnoreCase))

{

entry.ExtractToFile(Path.Combine(extractPath, entry.FullName));

}

}

}

}

}

}