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New Post: Top-level folder not appearing as ZipEntry within zip file

ronks — Tue, 18 Jun 2013 00:28:11 GMT

I'm seeing some odd behavior when I try to read a zip file and enumerate the contents. I'm using Visual Basic 10 on Windows 7, and Ionic.Zip.Reduced.dll version 1.9.1.8.

Basically DNZ doesn't recognize folders in the top level of the zip file. It recognizes the files within them, and also the subfolders within them and the files within those subfolders.

Say I have file TopLevelZip.zip structured like this:

File1 at the top level
File2 at the top level
FolderA at the top level containing

File3
File4

FolderB at the top level containing

FolderB2 at the next level containing
  - File5

Running this VB code:

  Using zip1 As ZipFile = ZipFile.Read(ZipToUnpack)
    Dim e As ZipEntry
    For Each e In zip1
      Debug.Print(e.Info)
    Next
  End Using

will return info on all five files, and FolderB2; but not FolderA or FolderB.
I would like to return as a ZipEntry each of those two missing folders at the top level, as well as what presently appears.
Any ideas?

New Post: "Garbage" files in directory crashing DotNetLib

waltermetcalf — Thu, 13 Jun 2013 20:35:22 GMT

Hi,

I'm trying to use DotNetZip to zip directories for back-up. I'm using the following script, based heavily one I found in the PowerShell examples.

[System.Reflection.Assembly]::LoadFrom('c:\Users\Walter\Documents\WindowsPowerShell\Modules\WalterMetcalf\DotNetZip\Ionic.Zip.dll');



$directoryToZip = 'c:\Users\Walter\Documents\';

$zipfile =  new-object Ionic.Zip.ZipFile;

$e= $zipfile.AddEntry("Readme.txt", "This is a zipfile created from within powershell.");

$e= $zipfile.AddDirectory($directoryToZip, "home");

$zipfile.Save("D:\ZipFiles-ps1-out.zip");

$zipfile.Dispose();

` The script give a "Access denied" exception error on a file called TV_Music.ini, supposedly in a sub-directory which doesn't contain it--UNTiL you turn on "Display Hidden Files" in Windows Explorer! During my testing I have had the exception occur on other files, which apparently don't exist.
I'm guessing these files are re-parse items, but turning off (=FALSE) the "WillTraverseReparsePoints" property only make the problem worse.

Any ideas, suggestions?

Thanks,
Walter

P.S. I'm using update 1.9.1.8 of the library; PS 3.0 on Windows 7 SP1

New Post: "Bad CRC32 in GZIP trailer" error if I don't read the whole stream

thezman — Tue, 04 Jun 2013 22:13:09 GMT

I found some time to dig into this.

Looking at the .Net version there is some CRC32 checking (see GZipDecoder.ReadFooter and Inflator.Decode if you have Reflector or equivalent). However that code only appear to be called as the stream is read and it gets to the end. However GZipStream doesn't override Close or Dispose so no checks are done when you do that.

The code in DotNetZip that says //read to end of file is not doing that at all. The checksum needs 8 bytes so if there's less than 8 bytes in the buffer it reads enough bytes of the next block so that it has 8 bytes.

My workaround for this is that I've pulled the DotNetZip source into my code and modified Close such that it takes a bool that allows me to disable the CRC check.

This is a tough one to 'fix'. Its clearly much safer to to the checksum but it would mean adding code to read the whole file apart from the last 8 bytes - I was unable to work out how to do this safely in my experiments. On a big file this could be expensive which makes it slower then the .Net version AND a different behavior in this scenario.

New Post: Classic ASP and .xlsx report

clef — Wed, 29 May 2013 17:23:05 GMT

Hi All, im new here and I just want to ask if someone has a good example of how to create an excel report using classic asp code and save it as .xlsx format. At this point i can generate .xls files but now I want to create the same report but in .xlsx format.

Is this possible using DotNetZip??

Thanks in advance.

New Post: How many threads will be created by Ionic?

jyotiranjanr — Mon, 27 May 2013 14:52:54 GMT

Hello,
I wanted to use Ionic in my project and just wanted to know will it create any extra threads? If it is creating extra threads, how can I see/monitor those threads.I wanted to use this in a Windows Service VS2010 application.

Note: I want to use "Ionic.Utils.Zip.Dll"

Thanks.

New Post: "Bad CRC32 in GZIP trailer" error if I don't read the whole stream

thezman — Sun, 26 May 2013 14:36:42 GMT

Thanks.... I wish it was that easy but I'm trying to read not write and there's plenty of disc space.. Hopefully it will help others though.

New Post: "Bad CRC32 in GZIP trailer" error if I don't read the whole stream

mjfulke — Sun, 26 May 2013 03:14:28 GMT

I read you post having the same problem. After about an hour I realized the drive I was writing to was out of space. I cleared off a bunch of space and now I don't get the error. Not sure this is your situation but I'm guessing this was one of those errors where the real problem is not evident in the error message.

New Post: Failure to extract a file from an encrypted archive

aaitken — Fri, 24 May 2013 14:59:47 GMT

Hi, has there been any progress with this issue?

I am also experiencing this with a particular set of files. Other sets of files decompress fine.
There are 3937 files and 3405 of them get unzipped successfully and it fails on the same file each time. Even if the files are compressed again the same thing happens.

New Post: MDF file is corrupt when extracting

bob0043 — Fri, 03 May 2013 18:46:40 GMT

This is caused by an error in the ParallelDeflate process that sets up a race condition.

Re: buffer size. The documentation (xml comments) says the buffer size is 128k but the code actually sets the buffer size to 64k. The problem appears to be a "race" condition that will mostly likely exhibit the problem if the input is an exact multiple of the buffers size but may occur even if it is not a multiple.

Please see https://dotnetzip.codeplex.com/workitem/14623 for further discussion and http://dotnetzip.codeplex.com/workitem/14087 for a complete analysis and fix for the problem.

As a side note: The "ZipFile" class in ZipFile.cs sets the default for ParallelDeflateThreshold to 512 * 1024 in _InitInstance. The "ZipOutputStream" class in ZipOutputStream.cs sets the default for ParallelDeflateThreshold to -1L in _Init. This leads to different default behavior where similar behavior might be expected.

New Post: how to remove directory structure from zip file

geac — Fri, 03 May 2013 17:49:54 GMT

Any support for discarding the directory structure of a zip file not created by DotNetZip, like the behavior of InfoZip's unzip -j flag?

Answered earlier, thank you:
https://dotnetzip.codeplex.com/discussions/83773

New Post: .docx files not readable after zip

dsullivan00 — Tue, 30 Apr 2013 19:10:25 GMT

I have an extracted docx file and I am trying to rezip them, but word is telling me the file is corrupt.

Am I approaching this the wrong way?

            zip.AddDirectory(path + "_rels",@"\_rels");
            zip.AddDirectory(path + "customXml", @"\customXml");
            zip.AddDirectory(path + "docProps", @"\dropProps");
            zip.AddDirectory(path + "word", @"\word");
            zip.AddFile(path + "[Content_Types].xml",@"\");
            zip.Save(path + "MyZipFile.docx");

New Post: OverflowException when accessing zip file twice

lolkuro — Tue, 30 Apr 2013 17:01:05 GMT

Hello everybody,

I started using DotNetZip in my application but I have problem when I want to use a zip file twice within my application. For example, first I read my zip file and display the content in my application.

using (ZipFile zip = ZipFile.Read(zipPath))
{
                       ...
}

Then later, I want to extract the same zip file, therefore I use the same code above and read the zip file into 'zip'. But then I receive an OverflowException:

Zip File Error: Cannot read that as a ZipFileSystem.OverflowException: overflow while creating filename
   at Ionic.Zip.ZipEntry.CopyHelper.AppendCopyToFileName(String f)
   at Ionic.Zip.ZipEntry.ReadDirEntry(ZipFile zf, Dictionary`2 previouslySeen)
   at Ionic.Zip.ZipFile.ReadCentralDirectory(ZipFile zf)
   at Ionic.Zip.ZipFile.ReadIntoInstance(ZipFile zf) ; File

When I close the application and start again, I can do the first step again but not the second. This happens to me every time I start reading to a zip file the second time.

Any idea why I get this exception? Thanks in advance.

New Post: Ionic.Zip.ZipException: Read error in file

tish11 — Mon, 29 Apr 2013 18:02:17 GMT

I am trying to extract a password-protected, split zip file -
And everytime I get the following exception error -
Ionic.Zip.ZipException: Read error in file

It returns this error at the Extractall statement.

Any help would be great!

New Post: IE10 fails to create zip file

Rob_Nagel — Fri, 26 Apr 2013 09:19:04 GMT

I have been using DotNetZip for a few years now, without incident.
With the release of IE10, the code fails, with error message "The (zipname) download was interrupted"
The code works fine in other browsers.

Can anyone help here please?

Code being used:

Response.Clear()
Response.BufferOutput = False

Dim archiveName As String = String.Format("{0}-" & Request("p") & ".zip", DateTime.Now.ToString("yyyy-MMM-dd-HHmmss"))

Response.ContentType = "application/zip"
Response.AddHeader("content-disposition", "filename=" + archiveName)

If HeaderSize <> 0 Then
Response.AddHeader("Content-Length", HeaderSize)
End If

Using zip As ZipFile = New ZipFile()

                zip.AddFiles(filesToInclude, "")
                zip.Save(Response.OutputStream)

End Using

Response.Close()

New Post: "Bad CRC32 in GZIP trailer" error if I don't read the whole stream

thezman — Thu, 25 Apr 2013 22:44:17 GMT

I'm using the GZipStream as a drop in replacement for the .Net one. For one operation I open with a binary reader and just read a string from the start of the file.

When i close the BinaryReader I get Bad CRC32 in GZIP trailer

Same question shows up from 2011 on Stack Overflow
http://stackoverflow.com/questions/7462220/am-i-really-forced-to-readtoend-a-streamreader-reading-an-ionic-zlib-gzipstrea

I'm running 1.9.1.8 - it worked with the .Net version but the .Net version doesn't run on the xbox and doesnt compress well.

This is the code:

using (var fs = File.Open(Filename, FileMode.Open, FileAccess.Read, FileShare.Read))
{
   using (var compress = new GZipStream(fs, CompressionMode.Decompress))
   {
     var reader = new BinaryReader(compress);
     Name = reader.ReadString();
     reader.Close();                            <--Exception happens here
     compress.Close();
  }
}

New Post: Cannnot compress multi byte filename.

megascus — Tue, 23 Apr 2013 02:12:20 GMT

I am using Ionic.Zip.dll v1.9.1.8 on Visual Studio 2008.

I want to include some multi byte filename(Japanese) to zip file in Windows 2008 Server.
The server's language setting is English.
I was prepared some file having multi byte filename.
But, there cannnot compressed.
(single byte filename can compressed.)

Please help.

New Post: Does using the DotNetZip (ionic.zip.dll) require admin privileges?

tknnguyen — Fri, 12 Apr 2013 14:07:38 GMT

Hi,

Here is the process I'm trying to do. I have a VB 2008 application, which connects to a SQL Server 2005 Express DB. This VB app has a feature that allows the user to backup the database. Database back up is nothing more than detaching the DB files, then make a copy of the DB files (.mdf, and .ldf), add the DB files to an archive (using DotNetZip), and lastly, re-attach the DB files again to the existing SQL Server instance.

What I have discovered is that even though the DB files (before attaching to SQL Server 2005 Express) has "Everyone" - "Full Control" in the ACL. After detaching it from SQL Server 2005 Express) the "Everyone" - "Full Control" has been removed from the ACL, thus, causing the ZIP process to crash, if I run the app as a Standard User in Windows 7 (with UAC enabled). I have discovered a way to make this work, which is after detaching the DB files, I would manually update the files' ACL to include "Everyone" - "Full Control"; then ZIP works just fine under Standard User in Windows.

Sorry for the long description. Hope it's not too confusing.

Thanks for the help.

Khoi.

New Post: Digital Signatures for Packages

alijmoor — Fri, 12 Apr 2013 00:33:57 GMT

Hi Zach

As far as I know there is no support for digitally signing .zip files, but this is because the .zip format itself does not support it

I can think of one workaround that would be to calculate a Hash value (fingerprint) of the .zip file data and then convert that hash value to base64 (readable text) and store that in the ZipFile Comment field.

Then to check if the file has been tampered with you could re-hash the data and compare it to the hash saved in the comment field

Just an idea

Hope it helps

New Post: Does using the DotNetZip (ionic.zip.dll) require admin privileges?

alijmoor — Fri, 12 Apr 2013 00:06:36 GMT

Hello

What type of file are you trying to add to the .zip file?

I have successfully used DotNetZip in several projects which are run by limited (non admin) users and have never experienced any problems when creating or extracting zip files.

Can you give more information on your use-case scenario please ?

Kind Regards
Alistair

New Post: Don't Include Parent Path

tamzak — Wed, 10 Apr 2013 22:28:29 GMT

If you mean adding files without it's full path?

zip.AddFile(@"C:/Users/Admin/Something.txt", String.Empty);

That will put it in the root of your zip file.