Zipping using System.IO.Compression

To use System.IO.Compression, you need to add a reference to WindowsBase.dll.

The following code snippet shows how to use some of the provided functionalities:

using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Packaging;

public static class ZipHelper
{
  public static void ZipFiles(string path, IEnumerable<string> files, 
         CompressionOption compressionLevel = CompressionOption.Normal)
  {
    using (FileStream fileStream = new FileStream(path, FileMode.Create))
    {
      ZipHelper.ZipFilesToStream(fileStream, files, compressionLevel);
    }
  }

  public static byte[] ZipFilesToByteArray(IEnumerable<string> files, 
         CompressionOption compressionLevel = CompressionOption.Normal)
  {
    byte[] zipBytes = default(byte[]);
    using (MemoryStream memoryStream = new MemoryStream())
    {
      ZipHelper.ZipFilesToStream(memoryStream, files, compressionLevel);
      memoryStream.Flush();
      zipBytes = memoryStream.ToArray();
    }

    return zipBytes;
  }

  public static void Unzip(string zipPath, string baseFolder)
  {
    using (FileStream fileStream = new FileStream(zipPath, FileMode.Open))
    {
      ZipHelper.UnzipFilesFromStream(fileStream, baseFolder);
    }
  }

  public static void UnzipFromByteArray(byte[] zipData, string baseFolder)
  {
    using (MemoryStream memoryStream = new MemoryStream(zipData))
    {
      ZipHelper.UnzipFilesFromStream(memoryStream, baseFolder);
    }
  }

  private static void ZipFilesToStream(Stream destination, 
          IEnumerable<string> files, CompressionOption compressionLevel)
  {
    using (Package package = Package.Open(destination, FileMode.Create))
    {
      foreach (string path in files)
      {
        // fix for white spaces in file names (by ErrCode)
        Uri fileUri = PackUriHelper.CreatePartUri(new Uri(@"/" + 
                      Path.GetFileName(path), UriKind.Relative));
        string contentType = @"data/" + ZipHelper.GetFileExtentionName(path);

        using (Stream zipStream = 
                package.CreatePart(fileUri, contentType, compressionLevel).GetStream())
        {
          using (FileStream fileStream = new FileStream(path, FileMode.Open))
          {
            fileStream.CopyTo(zipStream);
          }
        }
      }
    }
  }

  private static void UnzipFilesFromStream(Stream source, string baseFolder)
  {
    if (!Directory.Exists(baseFolder))
    {
      Directory.CreateDirectory(baseFolder);
    }

    using (Package package = Package.Open(source, FileMode.Open))
    {
      foreach (PackagePart zipPart in package.GetParts())
      {
        // fix for white spaces in file names (by ErrCode)
        string path = Path.Combine(baseFolder, 
             Uri.UnescapeDataString(zipPart.Uri.ToString()).Substring(1));

        using (Stream zipStream = zipPart.GetStream())
        {
          using (FileStream fileStream = new FileStream(path, FileMode.Create))
          {
            zipStream.CopyTo(fileStream);
          }
        }
      }
    }
  }

  private static string GetFileExtentionName(string path)
  {
    string extention = Path.GetExtension(path);
    if (!string.IsNullOrWhiteSpace(extention) && extention.StartsWith("."))
    {
      extention = extention.Substring(1);
    }

    return extention;
  }
}

Enjoy it!