Decompress old IMPLODE zip file with C#

Posted on 2009-04-20
Medium Priority
Last Modified: 2013-12-01
I've got some zip files coming from a very old mainframe that I would like to decompress.  They will unzip with the built in windows "compressed folders" utility and older version of winzip (I read that version 12 no longer supports deflate), but I want to automate it.  Free libs like SharpZipLib or ZipLib are out as they are mostly based on the built in (and much more common) "deflate" algorithm.  Can anybody direct me to a component that will handle the decompression of these files?  I'd even settle for the shareware command line version of pkunzip if such a thing exists anymore (although a component would be my first choice).
Question by:b_levitt
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Author Comment

ID: 24190896
By the way 7zip seems to be my command line option:

I'd still be interested in a component though.

Expert Comment

ID: 24408200

Expert Comment

ID: 24408206
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Author Comment

ID: 24440135
Just about anything recent regarding creating zip files uses the 'deflate' algorithm.  These old files I have were zipped using implode (the old pkzip format).  I doubt anything exists but I thought I would ask.

Accepted Solution

zwei earned 1400 total points
ID: 24440351
Sorry, I didn't read the question carefully. No, there's no library to do this kind of thing that I know of, but since you can do it from the command line with 7-zip you can use Process instead:

foreach (FileInfo fileInfo in DirecInfo.GetFiles("*.zip"))
       Process process = new Process();
       process.StartInfo.FileName = @"C:\Program Files\7-zip\7z.exe";
       process.StartInfo.Arguments = @" e C:\Directory\" + fileInfo.Name + @" -oC:\Directory";

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Assisted Solution

MogalManic earned 600 total points
ID: 24441255
Here is the tech. specs for the old zip formats:
you COULD write your own implementation.  

Or try the file against all of the various zip libraries out on the net
   http://www.info-zip.org/UnZip.html (library only, you would have to write a PINVOKE wrapper)
Here is a thread asking the same question:
You could use the 7zip librarys in c# code:
LVL 11

Author Closing Comment

ID: 31572570
Thanks for the effort zwei.  Thanks for a couple of those links Mogal.

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