Decompressing password-protected ZIP files with .NET 4.5

Question

Microsoft introduces improvements for ZIP file handling in .NET 4.5 in the System.IO.Compression namespace. Namely the classes ZipArchive and ZipFile. However, I have not y

Answer 1

For those targeting .Net Standard 2.0, SharpZipLib does a great work, handling gracefully extraction of in memory password protected zip files to byte[].

https://github.com/icsharpcode/SharpZipLib

Tried Ionic for the same scenario but was enable to extract files with the ZipInputStream, which generated corrupt extracted byte arrays.

Answer 2

I found the way is very simple to unzip in c#
Install PM (you can find new version if available!)

Install-Package Ionic.Zip -Version 1.9.1.8

Code C#

string zipFile = @"C:\Users\Fesslersoft\Desktop\ZipTest\Test.zip";
string targetDirectory = @"C:\Users\Fesslersoft\Desktop\ZipTest\";
 
using (Ionic.Zip.ZipFile zip = Ionic.Zip.ZipFile.Read(zipFile))
{
    zip.Password = "1234";
    zip.ExtractAll(targetDirectory, Ionic.Zip.ExtractExistingFileAction.DoNotOverwrite);
}
 
Console.WriteLine("Zip file has been successfully extracted.");
Console.Read();

Source: https://codesnippets.fesslersoft.de/extract-a-password-protected-zip-file-using-dotnetzip/

Answer 3

The ionic method is awesome. I tried three other approaches, and it is by far the best. Don't waste time, just use it.

https://dotnetzip.codeplex.com/wikipage?title=PS-Examples

Supports password encrypted, and other zip options.

Answer 4

There does not appear to be any support for password protected zip files in the native .net 4.5 library, similar to how there does not appear to be support in windows explorer, even with Windows 10! Some people have reported that they have zip corruption issues using the 3rd party DotNetLib, so make sure you extensively test if you do go down that path or try SharpZipLib instead.

Answer 5

Unfortunately not. There is no support within the .Net Framework 4.5 for password protected zip files. In this case you have to switch to one of the well known 3rd party libraries.

Answer 6

In looking at the methods provided by the 4.5 framework there is not a method that allows passwords with zip files. As mentioned in your question 3rd party is going to be your best bet.