Creating a Zip File in C#

I recently ran into a request in a project where I needed to zip up a number of files on the fly and email them to a specific individual. The email part was easy but I thought that the zip file part of the request would be a bit more difficult. I mean there is SharpZipLib, but that uses the GPL and that instantly killed that as an option for this product (I didn't make that requirement, it was forced upon me). At that point I thought that I was rather screwed until I found out that .Net has the ability to create zip files built into the system. Specifically if you look at the System.IO.Packaging portion of .Net (which is in the winbase DLL), you will find the ZipPackage class. This class, plus a couple others, allows you to package files together (by default into a zip file). So I spent about an hour and created a basic class to accomplish what I needed:

/\*
Copyright (c) 2011 <a href="http://www.gutgames.com">James Craig</a>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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THE SOFTWARE.\*/
  
#region Usings
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO.Packaging;
using System.IO;
#endregion
  
namespace Utilities.FileFormats.Zip
{
    /// <summary>
    /// Helper class for dealing with zip files
    /// </summary>
    public class ZipFile : IDisposable
    {
        #region Constructor
  
        /// <summary>
        /// Constructor
        /// </summary>
        /// <param name="FilePath">Path to the zip file</param>
        /// <param name="Overwrite">Should the zip file be overwritten?</param>
        public ZipFile(string FilePath, bool Overwrite)
        {
            if (string.IsNullOrEmpty(FilePath))
                throw new ArgumentNullException("FilePath");
            ZipFileStream = new FileStream(FilePath, Overwrite ? FileMode.Create : FileMode.OpenOrCreate);
        }
  
        #endregion
  
        #region Properties
  
        /// <summary>
        /// Zip file's FileStream
        /// </summary>
        protected virtual FileStream ZipFileStream { get; set; }
  
        #endregion
  
        #region Functions
  
        /// <summary>
        /// Adds a folder to the zip file
        /// </summary>
        /// <param name="Folder">Folder to add</param>
        public virtual void AddFolder(string Folder)
        {
            if (string.IsNullOrEmpty(Folder))
                throw new ArgumentNullException("Folder");
            if (Folder.EndsWith(@"\\"))
                Folder = Folder.Remove(Folder.Length - 1);
            using (Package Package = ZipPackage.Open(ZipFileStream, FileMode.OpenOrCreate))
            {
                List<FileInfo> Files = Utilities.IO.FileManager.FileList(Folder, true);
                foreach (FileInfo File in Files)
                {
                    string FilePath = File.FullName.Replace(Folder, "");
                    AddFile(FilePath, File, Package);
                }
            }
        }
  
        /// <summary>
        /// Adds a file to the zip file
        /// </summary>
        /// <param name="File">File to add</param>
        public virtual void AddFile(string File)
        {
            if (string.IsNullOrEmpty(File))
                throw new ArgumentNullException("File");
            if (!Utilities.IO.FileManager.FileExists(File))
                throw new ArgumentException("File");
            using (Package Package = ZipPackage.Open(ZipFileStream))
            {
                AddFile(File, new FileInfo(File), Package);
            }
        }
  
        /// <summary>
        /// Uncompresses the zip file to the specified folder
        /// </summary>
        /// <param name="Folder">Folder to uncompress the file in</param>
        public virtual void UncompressFile(string Folder)
        {
            if (string.IsNullOrEmpty(Folder))
                throw new ArgumentNullException(Folder);
            Utilities.IO.FileManager.CreateDirectory(Folder);
            using (Package Package = ZipPackage.Open(ZipFileStream, FileMode.Open, FileAccess.Read))
            {
                foreach (PackageRelationship Relationship in Package.GetRelationshipsByType("http://schemas.microsoft.com/opc/2006/sample/document"))
                {
                    Uri UriTarget = PackUriHelper.ResolvePartUri(new Uri("/", UriKind.Relative), Relationship.TargetUri);
                    PackagePart Document = Package.GetPart(UriTarget);
                    Extract(Document, Folder);
                }
                if (File.Exists(Folder + @"\\\[Content\_Types\].xml"))
                    File.Delete(Folder + @"\\\[Content\_Types\].xml");
            }
        }
  
        /// <summary>
        /// Extracts an individual file
        /// </summary>
        /// <param name="Document">Document to extract</param>
        /// <param name="Folder">Folder to extract it into</param>
        protected virtual void Extract(PackagePart Document, string Folder)
        {
            if (string.IsNullOrEmpty(Folder))
                throw new ArgumentNullException(Folder);
            string Location = Folder + System.Web.HttpUtility.UrlDecode(Document.Uri.ToString()).Replace('\\\\', '/');
            Utilities.IO.FileManager.CreateDirectory(Path.GetDirectoryName(Location));
            byte\[\] Data = new byte\[1024\];
            using (FileStream FileStream = new FileStream(Location, FileMode.Create))
            {
                Stream DocumentStream = Document.GetStream();
                while (true)
                {
                    int Size = DocumentStream.Read(Data, 0, 1024);
                    FileStream.Write(Data, 0, Size);
                    if (Size != 1024)
                        break;
                }
                FileStream.Close();
            }
        }
  
        /// <summary>
        /// Adds a file to the zip file
        /// </summary>
        /// <param name="File">File to add</param>
        /// <param name="FileInfo">File information</param>
        /// <param name="Package">Package to add the file to</param>
        protected virtual void AddFile(string File, FileInfo FileInfo, Package Package)
        {
            if (string.IsNullOrEmpty(File))
                throw new ArgumentNullException("File");
            if (!Utilities.IO.FileManager.FileExists(FileInfo.FullName))
                throw new ArgumentException("File");
            Uri UriPath = PackUriHelper.CreatePartUri(new Uri(File, UriKind.Relative));
            PackagePart PackagePart = Package.CreatePart(UriPath, System.Net.Mime.MediaTypeNames.Text.Xml, CompressionOption.Maximum);
            byte\[\] Data = null;
            Utilities.IO.FileManager.GetFileContents(FileInfo.FullName, out Data);
            PackagePart.GetStream().Write(Data, 0, Data.Count());
            Package.CreateRelationship(PackagePart.Uri, TargetMode.Internal, "http://schemas.microsoft.com/opc/2006/sample/document");
        }
  
        #endregion
  
        #region IDisposable Members
  
        public void Dispose()
        {
            if (ZipFileStream != null)
            {
                ZipFileStream.Close();
                ZipFileStream.Dispose();
                ZipFileStream = null;
            }
        }
  
        #endregion
    }
}

If you'll notice there isn't much actual code there. Just an AddFolder function, AddFile, and Uncompress (plus two protected functions that they use). In order to use it you just create the object like this:

using (Utilities.FileFormats.Zip.ZipFile File = new Utilities.FileFormats.Zip.ZipFile("ZIPFILENAME.zip", true))
{
    File.AddFolder("FOLDERTOADD");
}

And that's it, you add the files/folders that you want to the zip file and you're done (the ZipFile class actually handles outputting everything to a file). And we can unzip the file with the following code:

using (Utilities.FileFormats.Zip.ZipFile File = new Utilities.FileFormats.Zip.ZipFile("ZIPFILENAME.zip", false))
{
    File.UncompressFile("FOLDERTOUNCOMPRESSWITHIN");
}

And that's it. It accomplished what I needed and was extremely simple. Note that the code above doesn't work on all zip files but the zip files that you create can be opened with other apps. Anyway, try out the code (you may want to go to my utility library's site and check for updates as I've added the code there), leave feedback, and happy coding.

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