Develop Reference

sharpziplib FastZip extract rar error cannot find central directory c#

i want to extract RAR file using FastZip, here is my code :
FastZip fastZip = new FastZip();
fastZip.CreateEmptyDirectories = true;
if (password != "")
{
fastZip.Password = password;
}
string fileFilter = null;
fastZip.ExtractZip(CompressedFilePathValue, OutputFolderPathValue, fileFilter);
but i always get error:
cannot find central directory
the RAR file is ok,i open it with WinRAR without error, so how to extract RAR file using sharpziplib with FastZip or without FastZip?
Note: I do not want to use SharpCompress because i dose not support password.
Any way to extract RAR file using sharpziplib?
Thanks for help

here is how to extract RAR file ,without error cannot find central directory:
using (Stream fs = File.OpenRead(CompressedFilePathValue))
using (var zf = new ZipFile(fs))
{
if (!String.IsNullOrEmpty(password))
{
// AES encrypted entries are handled automatically
zf.Password = password;
}
foreach (ZipEntry zipEntry in zf)
{
if (!zipEntry.IsFile)
{
// Ignore directories
continue;
}
String entryFileName = zipEntry.Name;
// to remove the folder from the entry:
//entryFileName = Path.GetFileName(entryFileName);
// Optionally match entrynames against a selection list here
// to skip as desired.
// The unpacked length is available in the zipEntry.Size property.
// Manipulate the output filename here as desired.
var fullZipToPath = Path.Combine(OutputFolderPathValue, entryFileName);
var directoryName = Path.GetDirectoryName(fullZipToPath);
if (directoryName.Length > 0)
{
Directory.CreateDirectory(directoryName);
}
// 4K is optimum
var buffer = new byte[4096];
// Unzip file in buffered chunks. This is just as fast as unpacking
// to a buffer the full size of the file, but does not waste memory.
// The "using" will close the stream even if an exception occurs.
using (var zipStream = zf.GetInputStream(zipEntry))
using (Stream fsOutput = File.Create(fullZipToPath))
{
StreamUtils.Copy(zipStream, fsOutput, buffer);
}
}
}
To be honest this work only with rar file created with sharpziplib , it does not open rar created with winrar

how to fix Xamarin.forms System.IO.FileNotFoundException: Could not find file

I am using xamrin.forms, and I am trying to access file and read it.
I have lastusername.txt as text file and I set the build action for it as "Content", actually I am trying to read file as the following:
var filename = System.IO.Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Personal), "lastusername.txt");
if (filename != null)
return System.IO.File.ReadAllText(filename);//error occurred here
else
return "";
I get the following Error:
System.IO.FileNotFoundException: Could not find file

Place your file within the Android Assets folder and assign it with a build type of "AndroidAsset".
Since your app's assets are read-only, you can then read it via the AssetManager, saving (copy) it somewhere else if it does not exist (i.e. the first time the app is run):
var fileName = "MyAssetBasedFile.txt";
if (!File.Exists(Path.Combine(CacheDir.Path, fileName)))
{
AssetManager assets = this.Assets;
using (StreamReader sr = new StreamReader(assets.Open(fileName)))
using (StreamWriter sw = new StreamWriter(Path.Combine(CacheDir.Path, fileName), append: false))
sw.Write(sr.ReadToEnd());
}
string content;
using (StreamReader sr = new StreamReader(Path.Combine(CacheDir.Path, fileName)))
{
content = sr.ReadToEnd();
}
Log.Debug("SO", content);
The next time the app runs you will pick up the one in your cache dir.

How to read data from a zip file without having to unzip the entire file

Is there anyway in .Net (C#) to extract data from a zip file without decompressing the complete file?
I possibly want to extract data (file) from the start of a zip file if the compression algorithm compress the file used was in a deterministic order.

With .Net Framework 4.5 (using ZipArchive):
using (ZipArchive zip = ZipFile.Open(zipfile, ZipArchiveMode.Read))
foreach (ZipArchiveEntry entry in zip.Entries)
if(entry.Name == "myfile")
entry.ExtractToFile("myfile");
Find "myfile" in zipfile and extract it.

DotNetZip is your friend here.
As easy as:
using (ZipFile zip = ZipFile.Read(ExistingZipFile))
{
ZipEntry e = zip["MyReport.doc"];
e.Extract(OutputStream);
}
(you can also extract to a file or other destinations).
Reading the zip file's table of contents is as easy as:
using (ZipFile zip = ZipFile.Read(ExistingZipFile))
{
foreach (ZipEntry e in zip)
{
if (header)
{
System.Console.WriteLine("Zipfile: {0}", zip.Name);
if ((zip.Comment != null) && (zip.Comment != ""))
System.Console.WriteLine("Comment: {0}", zip.Comment);
System.Console.WriteLine("\n{1,-22} {2,8} {3,5} {4,8} {5,3} {0}",
"Filename", "Modified", "Size", "Ratio", "Packed", "pw?");
System.Console.WriteLine(new System.String('-', 72));
header = false;
}
System.Console.WriteLine("{1,-22} {2,8} {3,5:F0}% {4,8} {5,3} {0}",
e.FileName,
e.LastModified.ToString("yyyy-MM-dd HH:mm:ss"),
e.UncompressedSize,
e.CompressionRatio,
e.CompressedSize,
(e.UsesEncryption) ? "Y" : "N");
}
}
Edited To Note: DotNetZip used to live at Codeplex. Codeplex has been shut down. The old archive is still available at Codeplex. It looks like the code has migrated to Github:
https://github.com/DinoChiesa/DotNetZip. Looks to be the original author's repo.
https://github.com/haf/DotNetZip.Semverd. This looks to be the currently maintained version. It's also packaged up an available via Nuget at https://www.nuget.org/packages/DotNetZip/

Something like this will list and extract the files one by one, if you want to use SharpZipLib:
var zip = new ZipInputStream(File.OpenRead(#"C:\Users\Javi\Desktop\myzip.zip"));
var filestream = new FileStream(#"C:\Users\Javi\Desktop\myzip.zip", FileMode.Open, FileAccess.Read);
ZipFile zipfile = new ZipFile(filestream);
ZipEntry item;
while ((item = zip.GetNextEntry()) != null)
{
Console.WriteLine(item.Name);
using (StreamReader s = new StreamReader(zipfile.GetInputStream(item)))
{
// stream with the file
Console.WriteLine(s.ReadToEnd());
}
}
Based on this example: content inside zip file

Here is how a UTF8 text file can be read from a zip archive into a string variable (.NET Framework 4.5 and up):
string zipFileFullPath = "{{TypeYourZipFileFullPathHere}}";
string targetFileName = "{{TypeYourTargetFileNameHere}}";
string text = new string(
(new System.IO.StreamReader(
System.IO.Compression.ZipFile.OpenRead(zipFileFullPath)
.Entries.Where(x => x.Name.Equals(targetFileName,
StringComparison.InvariantCulture))
.FirstOrDefault()
.Open(), Encoding.UTF8)
.ReadToEnd())
.ToArray());

the following code can read specific file as byte array :
using ZipArchive zipArchive = ZipFile.OpenRead(zipFilePath);
foreach(ZipArchiveEntry zipArchiveEntry in zipArchive.Entries)
{
if(zipArchiveEntry.Name.Equals(fileName,StringComparison.OrdinalIgnoreCase))
{
Stream stream = zipArchiveEntry.Open();
using MemoryStream memoryStream = new MemoryStream();
await stream.CopyToAsync(memoryStream);
return memoryStream.ToArray();
}
}

Zip files have a table of contents. Every zip utility should have the ability to query just the TOC. Or you can use a command line program like 7zip -t to print the table of contents and redirect it to a text file.

In such case you will need to parse zip local header entries. Each file, stored in zip file, has preceding Local File Header entry, which (normally) contains enough information for decompression, Generally, you can make simple parsing of such entries in stream, select needed file, copy header + compressed file data to other file, and call unzip on that part (if you don't want to deal with the whole Zip decompression code or library).

Creating an Epub file with a Zip library

HI All,
I am trying to zip up an Epub file i have made using c#
Things I have tried
Dot Net Zip http://dotnetzip.codeplex.com/
- DotNetZip works but epubcheck fails the resulting file (**see edit below)
ZipStorer zipstorer.codeplex.com
- creates an epub file that passes validation but the file won't open in Adobe Digital Editions
7 zip
- I have not tried this using c# but when i zip the file using there interface it tells me that the mimetype file name has a length of 9 and it should be 8
In all cases the mimetype file is the first file added to the archive and is not compressed
The Epub validator that I'am using is epubcheck http://code.google.com/p/epubcheck/
if anyone has succesfully zipped an epub file with one of these libraries please let me know how or if anyone has zipped an epub file successfully with any other open source zipping api that would also work.
EDIT
DotNetZip works, see accepted answer below.

If you need to control the order of the entries in the ZIP file, you can use DotNetZip and the ZipOutputStream.
You said you tried DotNetZip and it (the epub validator) gave you an error complaining about the mime type thing. This is probably because you used the ZipFile type within DotNetZip. If you use ZipOutputStream, you can control the ordering of the zip entries, which is apparently important for epub (I don't know the format, just surmising).
EDIT
I just checked, and the epub page on Wikipedia describes how you need to format the .epub file. It says that the mimetype file must contain specific text, must be uncompressed and unencrypted, and must appear as the first file in the ZIP archive.
Using ZipOutputStream, you would do this by setting CompressionLevel = None on that particular ZipEntry - that value is not the default.
Here's some sample code:
private void Zipup()
{
string _outputFileName = "Fargle.epub";
using (FileStream fs = File.Open(_outputFileName, FileMode.Create, FileAccess.ReadWrite ))
{
using (var output= new ZipOutputStream(fs))
{
var e = output.PutNextEntry("mimetype");
e.CompressionLevel = CompressionLevel.None;
byte[] buffer= System.Text.Encoding.ASCII.GetBytes("application/epub+zip");
output.Write(buffer,0,buffer.Length);
output.PutNextEntry("META-INF/container.xml");
WriteExistingFile(output, "META-INF/container.xml");
output.PutNextEntry("OPS/"); // another directory
output.PutNextEntry("OPS/whatever.xhtml");
WriteExistingFile(output, "OPS/whatever.xhtml");
// ...
}
}
}
private void WriteExistingFile(Stream output, string filename)
{
using (FileStream fs = File.Open(fileName, FileMode.Read))
{
int n = -1;
byte[] buffer = new byte[2048];
while ((n = fs.Read(buffer,0,buffer.Length)) > 0)
{
output.Write(buffer,0,n);
}
}
}
See the documentation for ZipOutputStream here.

Why not make life easier?
private void IonicZip()
{
string sourcePath = "C:\\pulications\\";
string fileName = "filename.epub";
// Creating ZIP file and writing mimetype
using (ZipOutputStream zs = new ZipOutputStream(sourcePath + fileName))
{
var o = zs.PutNextEntry("mimetype");
o.CompressionLevel = CompressionLevel.None;
byte[] mimetype = System.Text.Encoding.ASCII.GetBytes("application/epub+zip");
zs.Write(mimetype, 0, mimetype.Length);
}
// Adding META-INF and OEPBS folders including files
using (ZipFile zip = new ZipFile(sourcePath + fileName))
{
zip.AddDirectory(sourcePath + "META-INF", "META-INF");
zip.AddDirectory(sourcePath + "OEBPS", "OEBPS");
zip.Save();
}
}

For anyone like me who's searching for other ways to do this, I would like to add that the ZipStorer class from Jaime Olivares is a great alternative. You can copy the code right into your project, and it's very easy to choose between 'deflate' and 'store'.
https://github.com/jaime-olivares/zipstorer
Here's my code for creating an EPUB:
Dictionary<string, string> FilesToZip = new Dictionary<string, string>()
{
{ ConfigPath + #"mimetype", #"mimetype"},
{ ConfigPath + #"container.xml", #"META-INF/container.xml" },
{ OutputFolder + Name.Output_OPF_Name, #"OEBPS/" + Name.Output_OPF_Name},
{ OutputFolder + Name.Output_XHTML_Name, #"OEBPS/" + Name.Output_XHTML_Name},
{ ConfigPath + #"style.css", #"OEBPS/style.css"},
{ OutputFolder + Name.Output_NCX_Name, #"OEBPS/" + Name.Output_NCX_Name}
};
using (ZipStorer EPUB = ZipStorer.Create(OutputFolder + "book.epub", ""))
{
bool First = true;
foreach (KeyValuePair<string, string> File in FilesToZip)
{
if (First) { EPUB.AddFile(ZipStorer.Compression.Store, File.Key, File.Value, ""); First = false; }
else EPUB.AddFile(ZipStorer.Compression.Deflate, File.Key, File.Value, "");
}
}
This code creates a perfectly valid EPUB file. However, if you don't need to worry about validation, it seems most eReaders will accept an EPUB with a 'deflate' mimetype. So my previous code using .NET's ZipArchive produced EPUBs that worked in Adobe Digital Editions and a PocketBook.

SharpZipLib : Compressing a single file to a single compressed file

I am currently working with SharpZipLib under .NET 2.0 and via this I need to compress a single file to a single compressed archive. In order to do this I am currently using the following:
string tempFilePath = #"C:\Users\Username\AppData\Local\Temp\tmp9AE0.tmp.xml";
string archiveFilePath = #"C:\Archive\Archive_[UTC TIMESTAMP].zip";
FileInfo inFileInfo = new FileInfo(tempFilePath);
ICSharpCode.SharpZipLib.Zip.FastZip fZip = new ICSharpCode.SharpZipLib.Zip.FastZip();
fZip.CreateZip(archiveFilePath, inFileInfo.Directory.FullName, false, inFileInfo.Name);
This works exactly (ish) as it should, however while testing I have encountered a minor gotcha. Lets say that my temp directory (i.e. the directory that contains the uncompressed input file) contains the following files:
tmp9AE0.tmp.xml //The input file I want to compress
xxx_tmp9AE0.tmp.xml // Some other file
yyy_tmp9AE0.tmp.xml // Some other file
wibble.dat // Some other file
When I run the compression all the .xml files are included in the compressed archive. The reason for this is because of the final fileFilter parameter passed to the CreateZip method. Under the hood SharpZipLib is performing a pattern match and this also picks up the files prefixed with xxx_ and yyy_. I assume it would also pick up anything postfixed as well.
So the question is, how can I compress a single file with SharpZipLib? Then again maybe the question is how can I format that fileFilter so that the match can only ever pick up the file I want to compress and nothing else.
As an aside, is there any reason as to why System.IO.Compression not include a ZipStream class? (It only supports GZipStream)
EDIT : Solution (Derived from accepted answer from Hans Passant)
This is the compression method I implemented:
private static void CompressFile(string inputPath, string outputPath)
{
FileInfo outFileInfo = new FileInfo(outputPath);
FileInfo inFileInfo = new FileInfo(inputPath);
// Create the output directory if it does not exist
if (!Directory.Exists(outFileInfo.Directory.FullName))
{
Directory.CreateDirectory(outFileInfo.Directory.FullName);
}
// Compress
using (FileStream fsOut = File.Create(outputPath))
{
using (ICSharpCode.SharpZipLib.Zip.ZipOutputStream zipStream = new ICSharpCode.SharpZipLib.Zip.ZipOutputStream(fsOut))
{
zipStream.SetLevel(3);
ICSharpCode.SharpZipLib.Zip.ZipEntry newEntry = new ICSharpCode.SharpZipLib.Zip.ZipEntry(inFileInfo.Name);
newEntry.DateTime = DateTime.UtcNow;
zipStream.PutNextEntry(newEntry);
byte[] buffer = new byte[4096];
using (FileStream streamReader = File.OpenRead(inputPath))
{
ICSharpCode.SharpZipLib.Core.StreamUtils.Copy(streamReader, zipStream, buffer);
}
zipStream.CloseEntry();
zipStream.IsStreamOwner = true;
zipStream.Close();
}
}
}

This is an XY problem, just don't use FastZip. Follow the first example on this web page to avoid accidents.