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Using GZipStream to explore a zip file

Hello, I am writing a VB.NET program, and I'd like to just do a quick scan of a ZIP file to make sure it contains a small file called info.txt (and maybe look at the contents, not completely necessary). I'm not sure if I have to decompress it to do this -- I'd rather not because the entire ZIP file is pretty big.

I'm not sure if it is possible to inspect w/o extracting, OR to just extract a single file info.txt, w/o doing the very slow (since lots of big files) decompression.

Anyway, since it's VB.NET the

Imports System.IO.Compression

namespace is available to me, with the GZipStream class. The example code for this class talks about compression and decompression, but nothing more advanced like what I'm talking about (if possible). If it is possible, sample code would be appreciated.

Thanks VERY much.

teebon

Hi Ron,

You may use DotNetZip library to achieve what you wanted.

http://dotnetzip.codeplex.com/
http://dotnetzip.codeplex.com/wikipage?title=VB-Examples&referringTitle=Examples

Refer to the second link above for the VB examples where you can loop through the files in the zip file and check the name:

  For Each e In zip1               
          'Check the file name for e here, if it is info.txt
          if(e.FileName = "info.txt")
             'Do something
      Next

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RonMexico

ASKER

Thanks teebon... I'll take a look. I came across that library in google hits and also read that it probably pre-dated the addition of the System.IO.Compression namespace to .NET. I would prefer to use built-in namespaces if possible. Do you happen to know whether this can't be done with the built-in component?

Also this might be greedy, but does that library allow you to look at the contents of a file w/o decompressing the whole thing?

Thanks.

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teebon

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RonMexico

ASKER

Awesome, thanks! Was unable to find anything close to that helpful in sample code. Did you find that online or write it. Thanks either way...

RonMexico

ASKER

Oh... I see the link now. Don't know how I missed that. Thanks again!