How do I create 7-Zip archives with .NET?

Question

How can I create 7-Zip archives from my C# console application? I need to be able to extract the archives using the regular, widely available 7-Zip program.

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Here are my results with the examples provided as answers to this question

• "Shelling out" to 7z.exe - this is the simplest and most effective approach, and I can confirm that it works nicely. As workmad3 mentions, I just need to guarantee that 7z.exe is installed on all target machines, which is something I can guarantee.
• 7Zip in memory compression - this refers to compressing cookies "in-memory" before sending to the client; this method seems somewhat promising. The wrapper methods (wrapping the LZMA SDK) return type byte[]. When I write the byte[] array to a file, I can't extract it using 7-Zip (File.7z is not supported archive).
• 7zSharp Wrapper (found on CodePlex) - this wraps the 7z exe/LZMA SDK. I referenced the project from my app, and it successfully created some archive files, but I was unable to extract the files using the regular 7-Zip program (File.7z is not supported archive).
• 7Zip SDK aka LZMA SDK - I guess I'm not smart enough to figure out how to use this (which is why I posted here)... Any working code examples that demonstrate creating a 7zip archive that is able to be extracted by the regular 7zip program?
• CodeProject C# (.NET) Interface for 7-Zip Archive DLLs - only supports extracting from 7zip archives... I need to create them!
• SharpZipLib - According to their FAQ, SharpZipLib doesn't support 7zip.

Answer 1

If you can guarantee the 7-zip app will be installed (and in the path) on all target machines, you can offload by calling the command line app 7z. Not the most elegant solution but it is the least work.

Answer 2

EggCafe 7Zip cookie example This is an example (zipping cookie) with the DLL of 7Zip.

CodePlex Wrapper This is an open source project that warp zipping function of 7z.

7Zip SDK The official SDK for 7zip (C, C++, C#, Java) <---My suggestion

.Net zip library by SharpDevelop.net

CodeProject example with 7zip

SharpZipLib Many zipping

Answer 3

SevenZipSharp is another solution. Creates 7-zip archives...

Answer 4

Here's a complete working example using the SevenZip SDK in C#.

It will write, and read, standard 7zip files as created by the Windows 7zip application.

PS. The previous example was never going to decompress because it never wrote the required property information to the start of the file.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using SevenZip.Compression.LZMA;
using System.IO;
using SevenZip;

namespace VHD_Director
{
    class My7Zip
    {
        public static void CompressFileLZMA(string inFile, string outFile)
        {
            Int32 dictionary = 1 << 23;
            Int32 posStateBits = 2;
            Int32 litContextBits = 3; // for normal files
            // UInt32 litContextBits = 0; // for 32-bit data
            Int32 litPosBits = 0;
            // UInt32 litPosBits = 2; // for 32-bit data
            Int32 algorithm = 2;
            Int32 numFastBytes = 128;

            string mf = "bt4";
            bool eos = true;
            bool stdInMode = false;


            CoderPropID[] propIDs =  {
                CoderPropID.DictionarySize,
                CoderPropID.PosStateBits,
                CoderPropID.LitContextBits,
                CoderPropID.LitPosBits,
                CoderPropID.Algorithm,
                CoderPropID.NumFastBytes,
                CoderPropID.MatchFinder,
                CoderPropID.EndMarker
            };

            object[] properties = {
                (Int32)(dictionary),
                (Int32)(posStateBits),
                (Int32)(litContextBits),
                (Int32)(litPosBits),
                (Int32)(algorithm),
                (Int32)(numFastBytes),
                mf,
                eos
            };

            using (FileStream inStream = new FileStream(inFile, FileMode.Open))
            {
                using (FileStream outStream = new FileStream(outFile, FileMode.Create))
                {
                    SevenZip.Compression.LZMA.Encoder encoder = new SevenZip.Compression.LZMA.Encoder();
                    encoder.SetCoderProperties(propIDs, properties);
                    encoder.WriteCoderProperties(outStream);
                    Int64 fileSize;
                    if (eos || stdInMode)
                        fileSize = -1;
                    else
                        fileSize = inStream.Length;
                    for (int i = 0; i < 8; i++)
                        outStream.WriteByte((Byte)(fileSize >> (8 * i)));
                    encoder.Code(inStream, outStream, -1, -1, null);
                }
            }

        }

        public static void DecompressFileLZMA(string inFile, string outFile)
        {
            using (FileStream input = new FileStream(inFile, FileMode.Open))
            {
                using (FileStream output = new FileStream(outFile, FileMode.Create))
                {
                    SevenZip.Compression.LZMA.Decoder decoder = new SevenZip.Compression.LZMA.Decoder();

                    byte[] properties = new byte[5];
                    if (input.Read(properties, 0, 5) != 5)
                        throw (new Exception("input .lzma is too short"));
                    decoder.SetDecoderProperties(properties);

                    long outSize = 0;
                    for (int i = 0; i < 8; i++)
                    {
                        int v = input.ReadByte();
                        if (v < 0)
                            throw (new Exception("Can't Read 1"));
                        outSize |= ((long)(byte)v) << (8 * i);
                    }
                    long compressedSize = input.Length - input.Position;

                    decoder.Code(input, output, compressedSize, outSize, null);
                }
            }
        }

        public static void Test()
        {
            CompressFileLZMA("DiscUtils.pdb", "DiscUtils.pdb.7z");
            DecompressFileLZMA("DiscUtils.pdb.7z", "DiscUtils.pdb2");
        }
    }
}

Answer 5

I used the sdk.

eg:

using SevenZip.Compression.LZMA;
private static void CompressFileLZMA(string inFile, string outFile)
{
   SevenZip.Compression.LZMA.Encoder coder = new SevenZip.Compression.LZMA.Encoder();

   using (FileStream input = new FileStream(inFile, FileMode.Open))
   {
      using (FileStream output = new FileStream(outFile, FileMode.Create))
      {
          coder.Code(input, output, -1, -1, null);
          output.Flush();
      }
   }
}

Answer 6

 string zipfile = @"E:\Folderx\NPPES.zip";
 string folder = @"E:\TargetFolderx";

 ExtractFile(zipfile,folder);
public void ExtractFile(string source, string destination)
        {
            // If the directory doesn't exist, create it.
            if (!Directory.Exists(destination))
                Directory.CreateDirectory(destination);

            //string zPath = ConfigurationManager.AppSettings["FileExtactorEXE"];
          //  string zPath = Properties.Settings.Default.FileExtactorEXE; ;

            string zPath=@"C:\Program Files\7-Zip\7zG.exe";

            try
            {
                ProcessStartInfo pro = new ProcessStartInfo();
                pro.WindowStyle = ProcessWindowStyle.Hidden;
                pro.FileName = zPath;
                pro.Arguments = "x \"" + source + "\" -o" + destination;
                Process x = Process.Start(pro);
                x.WaitForExit();
            }
            catch (System.Exception Ex) { }
        }

Just Install 7 zip from source and pass the parameter to the method.

Thanks. Please like the answer.

Answer 7

Some additional test-info on @Orwellophile code using a 17.9MB textfile.
Using the property values in the code-example "as is" will have a HUGE negative impact on performance, it takes 14.16 sec.

Setting the properties to the following do the same job at 3.91 sec (i.a. the archive will have the same container info which is: you can extract and test the archive with 7zip but there are no filename information)

Native 7zip 2 sec.

CoderPropID[] propIDs =  {
  //CoderPropID.DictionarySize,
  //CoderPropID.PosStateBits,
  //CoderPropID.LitContextBits,
  //CoderPropID.LitPosBits,
  //CoderPropID.Algorithm,
  //CoderPropID.NumFastBytes,
  //CoderPropID.MatchFinder,
  CoderPropID.EndMarker
};
object[] properties = {
  //(Int32)(dictionary),
  //(Int32)(posStateBits),
  //(Int32)(litContextBits),
  //(Int32)(litPosBits),
  //(Int32)(algorithm),
  //(Int32)(numFastBytes),
  //mf,
  eos
};

I did another test using native 7zip and a 1,2GB SQL backup file (.bak)
7zip (maximum compression): 1 minute
LZMA SDK (@Orwellophile with above property-setting): 12:26 min :-(
Outputfile roughly same size.

So I guess I'll myself will use a solution based on the c/c++ engine, i.a. either call the 7zip executable from c# or use squid-box/SevenZipSharp, which is a wrapper around the 7zip c/c++ dll file, and seems to be the newest fork of SevenZipSharp. Haven't tested the wrapper, but I hope is perform just as the native 7zip. But hopefully it will give the possibility to compress stream also which you obvious cannot if you call the exe directly. Otherwise I guess there isn't mush advantage over calling the exe. The wrapper have some additional dependencies so it will not make your published project "cleaner".

By the way it seems the .Net Core team consider implementing LZMA in the system.io class in .Core ver. 5, that would be great!

(I know this is kind of a comment and not an answer but to be able to provide the code snippet it couldn't be a comment)

Answer 8

I use this code

                string PZipPath = @"C:\Program Files\7-Zip\7z.exe";
                string sourceCompressDir = @"C:\Test";
                string targetCompressName = @"C:\Test\abc.zip";
                string CompressName = targetCompressName.Split('\\').Last();
                string[] fileCompressList = Directory.GetFiles(sourceCompressDir, "*.*");

                    if (fileCompressList.Length == 0)
                    {
                        MessageBox.Show("No file in directory", "Important Message");
                        return;
                    }
                    string filetozip = null;
                    foreach (string filename in fileCompressList)
                    {
                        filetozip = filetozip + "\"" + filename + " ";
                    }

                    ProcessStartInfo pCompress = new ProcessStartInfo();
                    pCompress.FileName = PZipPath;
                    if (chkRequestPWD.Checked == true)
                    {
                        pCompress.Arguments = "a -tzip \"" + targetCompressName + "\" " + filetozip + " -mx=9" + " -p" + tbPassword.Text;
                    }
                    else
                    {
                        pCompress.Arguments = "a -tzip \"" + targetCompressName + "\" \"" + filetozip + "\" -mx=9";
                    }
                    pCompress.WindowStyle = ProcessWindowStyle.Hidden;
                    Process x = Process.Start(pCompress);
                    x.WaitForExit();

Answer 9

Install the NuGet package called SevenZipSharp.Interop

Then:

SevenZipBase.SetLibraryPath(@".\x86\7z.dll");
var compressor = new SevenZip.SevenZipCompressor();
var filesToCompress = Directory.GetFiles(@"D:\data\");
compressor.CompressFiles(@"C:\archive\abc.7z", filesToCompress);

Answer 10

These easiest way is to work with .zip files instead of .7z and use Dot Net Zip

When spinning off 7zip commands to shell there are other issues like user privileges, I had issue with SevenZipSharp.

Private Function CompressFile(filename As String) As Boolean
Using zip As New ZipFile()
    zip.AddFile(filename & ".txt", "")
    zip.Save(filename & ".zip")
End Using

Return File.Exists(filename & ".zip")
End Function

Answer 11

SharpCompress is in my opinion one of the smartest compression libraries out there. It supports LZMA (7-zip), is easy to use and under active development.

As it has LZMA streaming support already, at the time of writing it unfortunately only supports 7-zip archive reading. BUT archive writing is on their todo list (see readme). For future readers: Check to get the current status here: https://github.com/adamhathcock/sharpcompress/blob/master/FORMATS.md

Answer 12

Here is code to create and extract 7zip (based on LZMA SDK - C#)

Note: 7z archives created with same code can be unarchived. As code uses managed LZMA using earlier version of LZMA SDK