Unzipping a file error - c#

I am using the SharpZipLib open source .net library from www.icsharpcode.net
My goal is to unzip an xml file and read it into a dataset. However I get the following error reading the file into a dataset: "Data at the root level is invalid. Line 1, position 1."
I believe what is happening is the unzipping code is not releasing the file for the following reasons.
1.) If I unzip the file and exit the application. When I restart the app I CAN read the unzipped file into a dataset.
2.) If I read in the xml file right after writing it out (no zipping) then it works fine.
3.) If I write the dataset to xml, zip it up, unzip it, then attempt to read it back in I get the exception.
The code below is pretty straight forward. UnZipFile will return the name of the file just unzipped. Right below this call is the call to read it into a dataset. The variable fileToRead is the full path to the newly unzipped xml file.
string fileToRead = UnZipFile(filepath, DOViewerUploadStoreArea);
ds.ReadXml(fileToRead )
private string UnZipFile(string file, string dirToUnzipTo)
{
string unzippedfile = "";
try
{
ZipInputStream s = new ZipInputStream(File.OpenRead(file));
ZipEntry myEntry;
string tmpEntry = String.Empty;
while ((myEntry = s.GetNextEntry()) != null)
{
string directoryName = dirToUnzipTo;
string fileName = Path.GetFileName(myEntry.Name);
string fileWDir = directoryName + fileName;
unzippedfile = fileWDir;
FileStream streamWriter = File.Create(fileWDir);
int size = 4096;
byte[] data = new byte[4096];
while (true)
{
size = s.Read(data, 0, data.Length);
if (size > 0) { streamWriter.Write(data, 0, size); }
else { break; }
}
streamWriter.Close();
}
s.Close();
}
catch (Exception ex)
{
LogStatus.WriteErrorLog(ex, "ERROR", "DOViewer.UnZipFile");
}
return (unzippedfile);
}

Well, what does the final file look like? (compared to the original). You don't show the zipping code, which might be part of the puzzle, especially as you are partially swallowing the exception.
I would also try ensuring everything IDisposable is Dispose()d, ideally via using; also - in case the problem is with path construction, use Path.Combine. And note that if myEntry.Name contains sub-directories, you will need to create them manually.
Here's what I have - it works for unzipping ICSharpCode.SharpZipLib.dll:
private string UnZipFile(string file, string dirToUnzipTo)
{
string unzippedfile = "";
try
{
using(Stream inStream = File.OpenRead(file))
using (ZipInputStream s = new ZipInputStream(inStream))
{
ZipEntry myEntry;
byte[] data = new byte[4096];
while ((myEntry = s.GetNextEntry()) != null)
{
string fileWDir = Path.Combine(dirToUnzipTo, myEntry.Name);
string dir = Path.GetDirectoryName(fileWDir);
// note only supports a single level of sub-directories...
if (!Directory.Exists(dir)) Directory.CreateDirectory(dir);
unzippedfile = fileWDir; // note; returns last file if multiple
using (FileStream outStream = File.Create(fileWDir))
{
int size;
while ((size = s.Read(data, 0, data.Length)) > 0)
{
outStream.Write(data, 0, size);
}
outStream.Close();
}
}
s.Close();
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
return (unzippedfile);
}
It could also be that the problem is either in the code that writes the zip, or the code that reads the generated file.

I compared the original with the final using TextPad and they are identical.
Also I rewrote the code to take advantage of the using. Here is the code.
My issue seems to be centered around file locking or something. If I unzip the file quit the application then start it up it will read find.
private string UnZipFile(string file, string dirToUnzipTo)
{
string unzippedfile = "";
try
{
using (ZipInputStream s = new ZipInputStream(File.OpenRead(file)))
{
ZipEntry theEntry;
while ((theEntry = s.GetNextEntry()) != null)
{
string directoryName = dirToUnzipTo;
string fileName = Path.GetFileName(theEntry.Name);
string fileWDir = directoryName + fileName;
unzippedfile = fileWDir;
if (fileName != String.Empty)
{
using (FileStream streamWriter = File.Create(fileWDir))
{
int size = 2048;
byte[] data = new byte[2048];
while (true)
{
size = s.Read(data, 0, data.Length);
if (size > 0)
{
streamWriter.Write(data, 0, size);
}
else
{
break;
}
}
}
}
}
}
}
catch (Exception ex)
{
LogStatus.WriteErrorLog(ex, "ERROR", "DOViewer.UnZipFile");
}
return (unzippedfile);
}

This is a lot simpler to do with DotNetZip.
using (ZipFile zip = ZipFile.Read(ExistingZipFile))
{
zip.ExtractAll(TargetDirectory);
}
If you want to decide on which files to extract ....
using (ZipFile zip = ZipFile.Read(ExistingZipFile))
{
foreach (ZipEntry e in zip)
{
if (wantThisFile(e.FileName)) e.Extract(TargetDirectory);
}
}
If you would like to overwrite existing files during extraction:
using (ZipFile zip = ZipFile.Read(ExistingZipFile))
{
zip.ExtractAll(TargetDirectory, ExtractExistingFileAction.OverwriteSilently);
}
Or, to extract password-protected entries:
using (ZipFile zip = ZipFile.Read(ExistingZipFile))
{
zip.Password = "Shhhh, Very Secret!";
zip.ExtractAll(TargetDirectory, ExtractExistingFileAction.OverwriteSilently);
}

Related

Splitting of text file not working properly in c#

I have requirement of writing to text file.
If the file size exceeds 700MB, create new file & write to it.
I am currently writing data with “|” delimited from database to file & after that check the file size & splitting into multiple files, but the file splits in middle of the line.
It should write till end of line or start that particular line in new file .
I need to write the column names in the first line in the newly splited file.
I am new to c#, could you please suggest me the solution with the sample code.
Please find below code to splitting the file
private static void ReadWriteToFile(string fileNames)
{
string sourceFileName = fileNames;
string destFileLocation = Path.GetDirectoryName(fileNames);
int index = 0;
long maxFileSize = 700 * 1024 * 1024;
byte[] buffer = new byte[65536];
using (Stream source = File.OpenRead(sourceFileName))
{
while (source.Position < source.Length)
{
index++;
string newFileName = Path.Combine(destFileLocation, Path.GetFileNameWithoutExtension(sourceFileName));
newFileName += index.ToString() + Path.GetExtension(sourceFileName);
using (Stream destination = File.OpenWrite(newFileName))
{
while (destination.Position < maxFileSize)
{
int bytes = source.Read(buffer, 0, (int)Math.Min(maxFileSize, buffer.Length));
destination.Write(buffer, 0, bytes);
if (bytes < Math.Min(maxFileSize, buffer.Length))
{
break;
}
}
}
}
}
}
Thanks in advance.
Could you please let me know if there is any alternative best way to do this
Try this, a rewrite of a line file splitter i wrote in my beginning c# times.
(You only have to add the column header as a string in the beginning of a new file.)
private static void SplitAfterMBytes(int splitAfterMBytes, string filename)
{
// Variable for max. file size.
var maxFileSize = splitAfterMBytes * 1048576;
int fileCount = 0;
long byteCount = 0;
StreamWriter writer = null;
try
{
var inputFile = new FileInfo(filename);
var index = filename.LastIndexOf('.');
//get only the name of the file.
var fileStart = filename.Substring(0, index);
// get the file extension
var fileExtension = inputFile.Extension;
// generate a new file name.
var outputFile = fileStart + '_' + fileCount++ + fileExtension;
// file format is like: QS_201101_321.txt.
writer = new StreamWriter(outputFile);
using (var reader = new StreamReader(filename))
{
for (string str; (str = reader.ReadLine()) != null;)
{
byteCount = byteCount + System.Text.Encoding.Unicode.GetByteCount(str);
if (byteCount >= maxFileSize)
{
// max number of bytes reached
// write into the old file, without Newline,
// so that no extra line is written.
writer.Write(str);
// 1. close the actual file.
writer.Close();
// 2. open a new file with number incresed by 1.
outputFile = fileStart + '_' + fileCount++ + fileExtension;
writer = new StreamWriter(outputFile);
byteCount = 0; //reset the counter.
}
else
{
// Write into the old file.
// Use a Linefeed, because Write works without LF.
// like Java ;)
writer.Write(str);
writer.Write(writer.NewLine);
}
}
}
}
catch (Exception ex)
{
// do something useful, like: Console.WriteLine(ex.Message);
}
finally
{
writer.Dispose();
}
}

C# unzip a file: Error with 'Thumbs.db'

I wrote a program that unzip a file (.zip) using SharpZipLib...
The following code:
public void UnZip(string zipFilePath, string extractionPath)
{
FastZip fz = new FastZip();
fz.ExtractZip(zipFilePath, extractionPath, null);
}
I get the following Exception:
Additional information: The access to the path "C:\Program files (x86)\... Thumbs.db" was refused.
The program starts with Admin rights and the file "Thumbs.db" does not exist in the .zip archive.
Who knows further?
Greets and thanks!
I would ignore the "Thumbs.db" file as its an OS file.
Maybe something like this:
using ICSharpCode.SharpZipLib.Core;
using ICSharpCode.SharpZipLib.Zip;
public void ExtractZipFile(string archiveFilenameIn, string password, string outFolder) {
ZipFile zf = null;
try {
FileStream fs = File.OpenRead(archiveFilenameIn);
zf = new ZipFile(fs);
if (!String.IsNullOrEmpty(password)) {
zf.Password = password; // AES encrypted entries are handled automatically
}
foreach (ZipEntry zipEntry in zf) {
if (!zipEntry.IsFile) {
continue; // Ignore directories
}
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.
byte[] buffer = new byte[4096]; // 4K is optimum
Stream zipStream = zf.GetInputStream(zipEntry);
// Manipulate the output filename here as desired.
String fullZipToPath = Path.Combine(outFolder, entryFileName);
string directoryName = Path.GetDirectoryName(fullZipToPath);
if (directoryName.Length > 0)
Directory.CreateDirectory(directoryName);
// 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 (FileStream streamWriter = File.Create(fullZipToPath)) {
StreamUtils.Copy(zipStream, streamWriter, buffer);
}
}
} finally {
if (zf != null) {
zf.IsStreamOwner = true; // Makes close also shut the underlying stream
zf.Close(); // Ensure we release resources
}
}
}

Stream was not writeable (StreamWriter)

I'm trying to remove specific line from file on IsolatedStorage but I'm still receiving the "Stream was not writeable" from following method:
public async static void RemoveFavoriteFromFile(int id)
{
string favoriteFilename = Globals.FavoriteFilepath;
StorageFolder local = Windows.Storage.ApplicationData.Current.LocalFolder;
var folder = await local.GetFolderAsync("DataFolder");
var file = await folder.OpenStreamForReadAsync(Globals.FavoriteFilepath);
using (StreamReader sr = new StreamReader(file))
{
using (StreamWriter sw = new StreamWriter(file))
{
string line = null;
while ((line = sr.ReadLine()) != null)
{
if (String.Compare(line, id.ToString()) == 0)
continue;
sw.WriteLine(line);
}
}
}
}
on line using (StreamWriter sw = new StreamWriter(file))
Could anybody help me please?
Thanks in advance
EDIT: I would mainly ask you to advice me how to remove specific line from existing file, no matter what I created already. Main issue for me in meaning of understanding is that how to write/edit a file which I firstly need to read for finding the specific line.
Reading and writing to the same file at the same time is always a bad idea.
Either write to a swap file "filename_swap.txt". After it has finished writing the entire file, delete the original file and rename the "filename_swap.txt" to the original file (basically replacing it).
Or you can read the entire file into a buffer, close the file. Make your changes to said buffer then open the file again for writing. This time, write the entire content of the modified buffer.
So lets modularize your program
using System.Threading.Tasks;
// read the specific file into a string buffer
private async Task<string> ReadFileIntoBuffer(string fileName)
{
string buffer = ""; // our buffer
StorageFolder local = Windows.Storage.ApplicationData.Current.LocalFolder; // local folder
var folder = await local.GetFolderAsync("DataFolder"); // sub folder
// open the file for reading
using (Stream s = await folder.OpenStreamForReadAsync(fileName))
{
using (StreamReader sr = new StreamReader(s))
{
buffer = await sr.ReadToEndAsync();
}
}
// return the buffer
return buffer;
}
// write the string buffer to a specific file
private async Task<bool> WriteBufferToFile(string fileName, string buffer)
{
try
{
StorageFolder local = Windows.Storage.ApplicationData.Current.LocalFolder; // local folder
var folder = await local.GetFolderAsync("DataFolder"); // sub folder
// open the file for writing
using (Stream s = await folder.OpenStreamForWriteAsync(fileName, CreationCollisionOption.ReplaceExisting))
{
using (StreamWriter sw = new StreamWriter(s))
{
await sw.WriteAsync(buffer);
}
}
}
catch (Exception ex)
{
string error_message = ex.Message;
return false;
}
return true;
}
// New Delete Lines function based off your old one
private string DeleteLines(string input_buffer, int id)
{
string output_buffer = "";
using (StringReader sr = new StringReader(input_buffer))
{
while (true)
{
string line = sr.ReadLine();
if (line != null)
{
if (String.Compare(line, id.ToString()) == 0)
{
}
else
{
// add it to the output_buffer plus the newline
output_buffer += (line + "\n");
}
}
else
{
break;
}
}
}
return output_buffer;
}
If you have trouble understanding a problem it generally a good idea to break it into smaller parts and debug from there.

How to extract a folder from zip file using SharpZipLib?

I have a test.zip file which contains inside a Folder with a bunch of other files and folders in it.
I found SharpZipLib after figuring out that .gz / GzipStream was not the way to go since its only for individual files. More importantly, doing this is similar to using GZipStream meaning it will create a FILE. But I have whole folder zipped. How do I unzip to a
For some reason the example unzipping here is set to ignore directories, so I'm not totally sure how that is done.
Also, I need to use .NET 2.0 for accomplish this.
I think it is the easier way.
Default functionality (please look here for more info https://github.com/icsharpcode/SharpZipLib/wiki/FastZip)
it extract with folders.
code:
using System;
using ICSharpCode.SharpZipLib.Zip;
var zipFileName = #"T:\Temp\Libs\SharpZipLib_0860_Bin.zip";
var targetDir = #"T:\Temp\Libs\unpack";
FastZip fastZip = new FastZip();
string fileFilter = null;
// Will always overwrite if target filenames already exist
fastZip.ExtractZip(zipFileName, targetDir, fileFilter);
This is how I did it:
public void UnZipp(string srcDirPath, string destDirPath)
{
ZipInputStream zipIn = null;
FileStream streamWriter = null;
try
{
Directory.CreateDirectory(Path.GetDirectoryName(destDirPath));
zipIn = new ZipInputStream(File.OpenRead(srcDirPath));
ZipEntry entry;
while ((entry = zipIn.GetNextEntry()) != null)
{
string dirPath = Path.GetDirectoryName(destDirPath + entry.Name);
if (!Directory.Exists(dirPath))
{
Directory.CreateDirectory(dirPath);
}
if (!entry.IsDirectory)
{
streamWriter = File.Create(destDirPath + entry.Name);
int size = 2048;
byte[] buffer = new byte[size];
while ((size = zipIn.Read(buffer, 0, buffer.Length)) > 0)
{
streamWriter.Write(buffer, 0, size);
}
}
streamWriter.Close();
}
}
catch (System.Threading.ThreadAbortException lException)
{
// do nothing
}
catch (Exception ex)
{
throw (ex);
}
finally
{
if (zipIn != null)
{
zipIn.Close();
}
if (streamWriter != null)
{
streamWriter.Close();
}
}
}
It's sloppy but I hope it helps!

.Net Zip Up files

Whats the best way to zip up files using C#? Ideally I want to be able to seperate files into a single archive.
You can use DotNetZip to archieve this. It´s free to use in any application.
Here´s some sample code:
try
{
// for easy disposal
using (ZipFile zip = new ZipFile())
{
// add this map file into the "images" directory in the zip archive
zip.AddFile("c:\\images\\personal\\7440-N49th.png", "images");
// add the report into a different directory in the archive
zip.AddFile("c:\\Reports\\2008-Regional-Sales-Report.pdf", "files");
zip.AddFile("ReadMe.txt");
zip.Save("MyZipFile.zip");
}
}
catch (System.Exception ex1)
{
System.Console.Error.WriteLine("exception: " + ex1);
}
This is now built into the framework if you have version 4.5+
Otherwise, use Ionic.
Namespace is System.IO.Packaging.ZIPPackage.
See http://visualstudiomagazine.com/articles/2012/05/21/net-framework-gets-zip.aspx for a story.
Have you looked at SharpZipLib?
I believe you can build zip files with classes in the System.IO.Packaging namespace - but every time I've tried to look into it, I've found it rather confusing...
Take a look at this library:
http://www.icsharpcode.net/OpenSource/SharpZipLib/
It is pretty comprehensive, it deals with many formats, is open-source, and you can use in closed-source commercial applications.
It is very simple to use:
byte[] data1 = new byte[...];
byte[] data2 = new byte[...];
/*...*/
var path = #"c:\test.zip";
var zip = new ZipOutputStream(new FileStream(path, FileMode.Create))
{
IsStreamOwner = true
}
zip.PutNextEntry("File1.txt");
zip.Write(data1, 0, data1.Length);
zip.PutNextEntry("File2.txt");
zip.Write(data2, 0, data2.Length);
zip.Close();
zip.Dispose();
There are a few librarys around - the most popular of which are DotNetZip and SharpZipLib.
Hi i created two methods with the ShapLib library (you can download it here http://www.icsharpcode.net/opensource/sharpziplib/) that would like to share, they are very easy to use just pass source and target path (fullpath including folder/file and extension). Hope it help you!
//ALLYOURNAMESPACESHERE
using ...
//SHARPLIB
using ICSharpCode.SharpZipLib.Zip;
using ICSharpCode.SharpZipLib.Zip.Compression.Streams;
public static class FileUtils
{
/// <summary>
///
/// </summary>
/// <param name="sourcePath"></param>
/// <param name="targetPath"></param>
public static void ZipFile(string sourcePath, string targetPath)
{
string tempZipFilePath = targetPath;
using (FileStream tempFileStream = File.Create(tempZipFilePath, 1024))
{
using (ZipOutputStream zipOutput = new ZipOutputStream(tempFileStream))
{
// Zip with highest compression.
zipOutput.SetLevel(9);
DirectoryInfo directory = new DirectoryInfo(sourcePath);
foreach (System.IO.FileInfo file in directory.GetFiles())
{
// Get local path and create stream to it.
String localFilename = file.FullName;
//ignore directories or folders
//ignore Thumbs.db file since this probably will throw an exception
//another process could be using it. e.g: Explorer.exe windows process
if (!file.Name.Contains("Thumbs") && !Directory.Exists(localFilename))
{
using (FileStream fileStream = new FileStream(localFilename, FileMode.Open, FileAccess.Read, FileShare.Read))
{
// Read full stream to in-memory buffer.
byte[] buffer = new byte[fileStream.Length];
fileStream.Read(buffer, 0, buffer.Length);
// Create a new entry for the current file.
ZipEntry entry = new ZipEntry(file.Name);
entry.DateTime = DateTime.Now;
// set Size and the crc, because the information
// about the size and crc should be stored in the header
// if it is not set it is automatically written in the footer.
// (in this case size == crc == -1 in the header)
// Some ZIP programs have problems with zip files that don't store
// the size and crc in the header.
entry.Size = fileStream.Length;
fileStream.Close();
// Update entry and write to zip stream.
zipOutput.PutNextEntry(entry);
zipOutput.Write(buffer, 0, buffer.Length);
// Get rid of the buffer, because this
// is a huge impact on the memory usage.
buffer = null;
}
}
}
// Finalize the zip output.
zipOutput.Finish();
// Flushes the create and close.
zipOutput.Flush();
zipOutput.Close();
}
}
}
public static void unZipFile(string sourcePath, string targetPath)
{
if (!Directory.Exists(targetPath))
Directory.CreateDirectory(targetPath);
using (ZipInputStream s = new ZipInputStream(File.OpenRead(sourcePath)))
{
ZipEntry theEntry;
while ((theEntry = s.GetNextEntry()) != null)
{
if (theEntry.Name != String.Empty)
{
using (FileStream streamWriter = File.Create(targetPath + "\\" + theEntry.Name))
{
int size = 2048;
byte[] data = new byte[2048];
while (true)
{
size = s.Read(data, 0, data.Length);
if (size > 0)
{
streamWriter.Write(data, 0, size);
}
else
{
break;
}
}
}
}
}
}
}
}

Categories

Resources