Develop Reference

C# ZipArchive: zip file not created

I tried below code to first convert my bytes to compressed bytes and try to create a zip file, but file is not generated. Could someone please suggest!
byte[] result;
var X = 86251;
byte[] compressedBytes;
using (FileStream SourceStream = File.Open(filename, FileMode.Open))
{
SourceStream.Seek(0, SeekOrigin.Begin);
result = new byte[X];
await SourceStream.ReadAsync(result, 0, X);
}
string fileName = "Export_" + DateTime.Now.ToString("yyyyMMddhhmmss") + ".zip";
using (var outStream = new MemoryStream())
{
using (var archive = new ZipArchive(outStream, ZipArchiveMode.Create, true))
{
var fileInArchive = archive.CreateEntry(fileName, CompressionLevel.Optimal);
using (var entryStream = fileInArchive.Open())
using (var fileToCompressStream = new MemoryStream(result))
{
fileToCompressStream.CopyTo(entryStream);
}
}
compressedBytes = outStream.ToArray();
}

You're not creating an actual file anywhere. You're just writing to a memory stream. Change it to write to a file.
using (var outStream = new File.Create(fileName))
{
using (var archive = new ZipArchive(outStream, ZipArchiveMode.Create, true))
{
var fileInArchive = archive.CreateEntry(filename, CompressionLevel.Optimal);
using (var entryStream = fileInArchive.Open())
using (var fileToCompressStream = new MemoryStream(result))
{
fileToCompressStream.CopyTo(entryStream);
}
}
}

.NET Core Created Zip Archive is corrupted [duplicate]

I'm trying to create a ZIP archive with a simple demo text file using a MemoryStream as follows:
using (var memoryStream = new MemoryStream())
using (var archive = new ZipArchive(memoryStream , ZipArchiveMode.Create))
{
var demoFile = archive.CreateEntry("foo.txt");
using (var entryStream = demoFile.Open())
using (var streamWriter = new StreamWriter(entryStream))
{
streamWriter.Write("Bar!");
}
using (var fileStream = new FileStream(#"C:\Temp\test.zip", FileMode.Create))
{
stream.CopyTo(fileStream);
}
}
If I run this code, the archive file itself is created but foo.txt isn't.
However, if I replace the MemoryStream directly with the file stream, the archive is created correctly:
using (var fileStream = new FileStream(#"C:\Temp\test.zip", FileMode.Create))
using (var archive = new ZipArchive(fileStream, FileMode.Create))
{
// ...
}
Is it possible to use a MemoryStream to create the ZIP archive without the FileStream?

Thanks to ZipArchive creates invalid ZIP file, I got:
using (var memoryStream = new MemoryStream())
{
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
{
var demoFile = archive.CreateEntry("foo.txt");
using (var entryStream = demoFile.Open())
using (var streamWriter = new StreamWriter(entryStream))
{
streamWriter.Write("Bar!");
}
}
using (var fileStream = new FileStream(#"C:\Temp\test.zip", FileMode.Create))
{
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(fileStream);
}
}
That indicated we need to call Dispose on ZipArchive before we can use it, which as Amir suggests is likely because it writes final bytes like checksum to the archive that makes it complete. But in order not close the stream so we can re-use it after you need to pass true as the third parameter to ZipArchive.

Just another version of zipping without writing any file.
string fileName = "export_" + DateTime.Now.ToString("yyyyMMddhhmmss") + ".xlsx";
byte[] fileBytes = here is your file in bytes
byte[] compressedBytes;
string fileNameZip = "Export_" + DateTime.Now.ToString("yyyyMMddhhmmss") + ".zip";
using (var outStream = new MemoryStream())
{
using (var archive = new ZipArchive(outStream, ZipArchiveMode.Create, true))
{
var fileInArchive = archive.CreateEntry(fileName, CompressionLevel.Optimal);
using (var entryStream = fileInArchive.Open())
using (var fileToCompressStream = new MemoryStream(fileBytes))
{
fileToCompressStream.CopyTo(entryStream);
}
}
compressedBytes = outStream.ToArray();
}

Set the position of the stream to the 0 before copying it to the zip stream.
using (var memoryStream = new MemoryStream())
{
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
{
var demoFile = archive.CreateEntry("foo.txt");
using (var entryStream = demoFile.Open())
using (var streamWriter = new StreamWriter(entryStream))
{
streamWriter.Write("Bar!");
}
}
using (var fileStream = new FileStream(#"C:\Temp\test.zip", FileMode.Create))
{
memoryStream.Position=0;
memoryStream.WriteTo(fileStream);
}
}

Working solution for MVC
public ActionResult Index()
{
string fileName = "test.pdf";
string fileName1 = "test.vsix";
string fileNameZip = "Export_" + DateTime.Now.ToString("yyyyMMddhhmmss") + ".zip";
byte[] fileBytes = System.IO.File.ReadAllBytes(#"C:\test\test.pdf");
byte[] fileBytes1 = System.IO.File.ReadAllBytes(#"C:\test\test.vsix");
byte[] compressedBytes;
using (var outStream = new MemoryStream())
{
using (var archive = new ZipArchive(outStream, ZipArchiveMode.Create, true))
{
var fileInArchive = archive.CreateEntry(fileName, CompressionLevel.Optimal);
using (var entryStream = fileInArchive.Open())
using (var fileToCompressStream = new MemoryStream(fileBytes))
{
fileToCompressStream.CopyTo(entryStream);
}
var fileInArchive1 = archive.CreateEntry(fileName1, CompressionLevel.Optimal);
using (var entryStream = fileInArchive1.Open())
using (var fileToCompressStream = new MemoryStream(fileBytes1))
{
fileToCompressStream.CopyTo(entryStream);
}
}
compressedBytes = outStream.ToArray();
}
return File(compressedBytes, "application/zip", fileNameZip);
}

You need to finish writing the memory stream then read the buffer back.
using (var memoryStream = new MemoryStream())
{
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create))
{
var demoFile = archive.CreateEntry("foo.txt");
using (var entryStream = demoFile.Open())
using (var streamWriter = new StreamWriter(entryStream))
{
streamWriter.Write("Bar!");
}
}
using (var fileStream = new FileStream(#"C:\Temp\test.zip", FileMode.Create))
{
var bytes = memoryStream.GetBuffer();
fileStream.Write(bytes,0,bytes.Length );
}
}

using System;
using System.IO;
using System.IO.Compression;
namespace ConsoleApplication
{
class Program`enter code here`
{
static void Main(string[] args)
{
using (FileStream zipToOpen = new FileStream(#"c:\users\exampleuser\release.zip", FileMode.Open))
{
using (ZipArchive archive = new ZipArchive(zipToOpen, ZipArchiveMode.Update))
{
ZipArchiveEntry readmeEntry = archive.CreateEntry("Readme.txt");
using (StreamWriter writer = new StreamWriter(readmeEntry.Open()))
{
writer.WriteLine("Information about this package.");
writer.WriteLine("========================");
}
}
}
}
}
}

Function to return stream that contain zip file
public static Stream ZipGenerator(List<string> files)
{
ZipArchiveEntry fileInArchive;
Stream entryStream;
int i = 0;
List<byte[]> byteArray = new List<byte[]>();
foreach (var file in files)
{
byteArray.Add(File.ReadAllBytes(file));
}
var outStream = new MemoryStream();
using (var archive = new ZipArchive(outStream, ZipArchiveMode.Create, true))
{
foreach (var file in files)
{
fileInArchive=(archive.CreateEntry(Path.GetFileName(file), CompressionLevel.Optimal));
using (entryStream = fileInArchive.Open())
{
using (var fileToCompressStream = new MemoryStream(byteArray[i]))
{
fileToCompressStream.CopyTo(entryStream);
}
i++;
}
}
}
outStream.Position = 0;
return outStream;
}
If you want , write zip to file stream.
using (var fileStream = new FileStream(#"D:\Tools\DBExtractor\DBExtractor\bin\Debug\test.zip", FileMode.Create))
{
outStream.Position = 0;
outStream.WriteTo(fileStream);
}
`

I'm late to the party, but there are scenarios where you can't access the ZipArchive's constructor to set the leaveOpen parameter and where you don't want the ZIP to be written to disk. In my case, the AsiceArchive class I'm using internally creates a ZipArchive but doesn't set leaveOpen to true.
I created a subclass of Stream that delegates all calls to an inner stream (a few clicks with ReSharper). This class is not disposable, so when the ZipArchive gets disposed, nothing happens to the inner stream.
public class NondisposingStreamWrapper : Stream
{
private readonly Stream _streamImplementation;
public NondisposingStreamWrapper(Stream inner) => _streamImplementation = inner;
public override void Flush() => _streamImplementation.Flush();
public override int Read(byte[] buffer, int offset, int count) => _streamImplementation.Read(buffer, offset, count);
public override long Seek(long offset, SeekOrigin origin) => _streamImplementation.Seek(offset, origin);
public override void SetLength(long value) => _streamImplementation.SetLength(value);
public override void Write(byte[] buffer, int offset, int count) => _streamImplementation.Write(buffer, offset, count);
public override bool CanRead => _streamImplementation.CanRead;
public override bool CanSeek => _streamImplementation.CanSeek;
public override bool CanWrite => _streamImplementation.CanWrite;
public override long Length => _streamImplementation.Length;
public override long Position
{
get => _streamImplementation.Position;
set => _streamImplementation.Position = value;
}
}
Use it like this:
using var memoryStream = new MemoryStream();
var output = new NondisposingStreamWrapper(memoryStream);
using (var archive = new ZipArchive(output, ZipArchiveMode.Create))
{
// add entries to archive
}
memoryStream.Flush();
memoryStream.Position = 0;
// write to file just for testing purposes
File.WriteAllBytes("out.zip", memoryStream.ToArray());

This is the way to convert a entity to XML File and then compress it:
private void downloadFile(EntityXML xml) {
string nameDownloadXml = "File_1.xml";
string nameDownloadZip = "File_1.zip";
var serializer = new XmlSerializer(typeof(EntityXML));
Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.AddHeader("content-disposition", "attachment;filename=" + nameDownloadZip);
using (var memoryStream = new MemoryStream())
{
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
{
var demoFile = archive.CreateEntry(nameDownloadXml);
using (var entryStream = demoFile.Open())
using (StreamWriter writer = new StreamWriter(entryStream, System.Text.Encoding.UTF8))
{
serializer.Serialize(writer, xml);
}
}
using (var fileStream = Response.OutputStream)
{
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(fileStream);
}
}
Response.End();
}

Just in case, if anyone wants to save a dynamic zip file through SaveFileDialog.
var logFileName = "zip_filename.zip";
appLogSaver.FileName = logFileName;
appLogSaver.Filter = "LogFiles|*.zip";
appLogSaver.DefaultExt = "zip";
DialogResult resDialog = appLogSaver.ShowDialog();
if (resDialog.ToString() == "OK")
{
System.IO.FileStream fs = (System.IO.FileStream)appLogSaver.OpenFile();
using (var memoryStream = new MemoryStream())
{
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
{
var demoFile = archive.CreateEntry("foo.txt");
using (var entryStream = demoFile.Open())
{
using (var streamWriter = new StreamWriter(entryStream))
{
//read your existing file and put the content here
streamWriter.Write("Bar!");
}
}
var demoFile2 = archive.CreateEntry("foo2.txt");
using (var entryStream = demoFile2.Open())
{
using (var streamWriter = new StreamWriter(entryStream))
{
streamWriter.Write("Bar2!");
}
}
}
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(fs);
}
fs.Close();
}

For me something like this was ok:
using (var memoryStream = new MemoryStream())
{
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
{
var file = archive.CreateEntry("file.json");
using var entryStream = file.Open();
using var streamWriter = new StreamWriter(entryStream);
streamWriter.WriteLine(someJsonLine);
}
}

private void button6_Click(object sender, EventArgs e)
{
//create With Input FileNames
AddFileToArchive_InputByte(new ZipItem[]{ new ZipItem( #"E:\b\1.jpg",#"images\1.jpg"),
new ZipItem(#"E:\b\2.txt",#"text\2.txt")}, #"C:\test.zip");
//create with input stream
AddFileToArchive_InputByte(new ZipItem[]{ new ZipItem(File.ReadAllBytes( #"E:\b\1.jpg"),#"images\1.jpg"),
new ZipItem(File.ReadAllBytes(#"E:\b\2.txt"),#"text\2.txt")}, #"C:\test.zip");
//Create Archive And Return StreamZipFile
MemoryStream GetStreamZipFile = AddFileToArchive(new ZipItem[]{ new ZipItem( #"E:\b\1.jpg",#"images\1.jpg"),
new ZipItem(#"E:\b\2.txt",#"text\2.txt")});
//Extract in memory
ZipItem[] ListitemsWithBytes = ExtractItems(#"C:\test.zip");
//Choese Files For Extract To memory
List<string> ListFileNameForExtract = new List<string>(new string[] { #"images\1.jpg", #"text\2.txt" });
ListitemsWithBytes = ExtractItems(#"C:\test.zip", ListFileNameForExtract);
// Choese Files For Extract To Directory
ExtractItems(#"C:\test.zip", ListFileNameForExtract, "c:\\extractFiles");
}
public struct ZipItem
{
string _FileNameSource;
string _PathinArchive;
byte[] _Bytes;
public ZipItem(string __FileNameSource, string __PathinArchive)
{
_Bytes=null ;
_FileNameSource = __FileNameSource;
_PathinArchive = __PathinArchive;
}
public ZipItem(byte[] __Bytes, string __PathinArchive)
{
_Bytes = __Bytes;
_FileNameSource = "";
_PathinArchive = __PathinArchive;
}
public string FileNameSource
{
set
{
FileNameSource = value;
}
get
{
return _FileNameSource;
}
}
public string PathinArchive
{
set
{
_PathinArchive = value;
}
get
{
return _PathinArchive;
}
}
public byte[] Bytes
{
set
{
_Bytes = value;
}
get
{
return _Bytes;
}
}
}
public void AddFileToArchive(ZipItem[] ZipItems, string SeveToFile)
{
MemoryStream memoryStream = new MemoryStream();
//Create Empty Archive
ZipArchive archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true);
foreach (ZipItem item in ZipItems)
{
//Create Path File in Archive
ZipArchiveEntry FileInArchive = archive.CreateEntry(item.PathinArchive);
//Open File in Archive For Write
var OpenFileInArchive = FileInArchive.Open();
//Read Stream
FileStream fsReader = new FileStream(item.FileNameSource, FileMode.Open, FileAccess.Read);
byte[] ReadAllbytes = new byte[4096];//Capcity buffer
int ReadByte = 0;
while (fsReader.Position != fsReader.Length)
{
//Read Bytes
ReadByte = fsReader.Read(ReadAllbytes, 0, ReadAllbytes.Length);
//Write Bytes
OpenFileInArchive.Write(ReadAllbytes, 0, ReadByte);
}
fsReader.Dispose();
OpenFileInArchive.Close();
}
archive.Dispose();
using (var fileStream = new FileStream(SeveToFile, FileMode.Create))
{
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(fileStream);
}
}
public MemoryStream AddFileToArchive(ZipItem[] ZipItems)
{
MemoryStream memoryStream = new MemoryStream();
//Create Empty Archive
ZipArchive archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true);
foreach (ZipItem item in ZipItems)
{
//Create Path File in Archive
ZipArchiveEntry FileInArchive = archive.CreateEntry(item.PathinArchive);
//Open File in Archive For Write
var OpenFileInArchive = FileInArchive.Open();
//Read Stream
FileStream fsReader = new FileStream(item.FileNameSource, FileMode.Open, FileAccess.Read);
byte[] ReadAllbytes = new byte[4096];//Capcity buffer
int ReadByte = 0;
while (fsReader.Position != fsReader.Length)
{
//Read Bytes
ReadByte = fsReader.Read(ReadAllbytes, 0, ReadAllbytes.Length);
//Write Bytes
OpenFileInArchive.Write(ReadAllbytes, 0, ReadByte);
}
fsReader.Dispose();
OpenFileInArchive.Close();
}
archive.Dispose();
return memoryStream;
}
public void AddFileToArchive_InputByte(ZipItem[] ZipItems, string SeveToFile)
{
MemoryStream memoryStream = new MemoryStream();
//Create Empty Archive
ZipArchive archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true);
foreach (ZipItem item in ZipItems)
{
//Create Path File in Archive
ZipArchiveEntry FileInArchive = archive.CreateEntry(item.PathinArchive);
//Open File in Archive For Write
var OpenFileInArchive = FileInArchive.Open();
//Read Stream
// FileStream fsReader = new FileStream(item.FileNameSource, FileMode.Open, FileAccess.Read);
byte[] ReadAllbytes = new byte[4096];//Capcity buffer
int ReadByte = 4096 ;int TotalWrite=0;
while (TotalWrite != item.Bytes.Length)
{
if(TotalWrite+4096>item.Bytes.Length)
ReadByte=item.Bytes.Length-TotalWrite;
Array.Copy(item.Bytes, TotalWrite, ReadAllbytes, 0, ReadByte);
//Write Bytes
OpenFileInArchive.Write(ReadAllbytes, 0, ReadByte);
TotalWrite += ReadByte;
}
OpenFileInArchive.Close();
}
archive.Dispose();
using (var fileStream = new FileStream(SeveToFile, FileMode.Create))
{
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(fileStream);
}
}
public MemoryStream AddFileToArchive_InputByte(ZipItem[] ZipItems)
{
MemoryStream memoryStream = new MemoryStream();
//Create Empty Archive
ZipArchive archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true);
foreach (ZipItem item in ZipItems)
{
//Create Path File in Archive
ZipArchiveEntry FileInArchive = archive.CreateEntry(item.PathinArchive);
//Open File in Archive For Write
var OpenFileInArchive = FileInArchive.Open();
//Read Stream
// FileStream fsReader = new FileStream(item.FileNameSource, FileMode.Open, FileAccess.Read);
byte[] ReadAllbytes = new byte[4096];//Capcity buffer
int ReadByte = 4096 ;int TotalWrite=0;
while (TotalWrite != item.Bytes.Length)
{
if(TotalWrite+4096>item.Bytes.Length)
ReadByte=item.Bytes.Length-TotalWrite;
Array.Copy(item.Bytes, TotalWrite, ReadAllbytes, 0, ReadByte);
//Write Bytes
OpenFileInArchive.Write(ReadAllbytes, 0, ReadByte);
TotalWrite += ReadByte;
}
OpenFileInArchive.Close();
}
archive.Dispose();
return memoryStream;
}
public void ExtractToDirectory(string sourceArchiveFileName, string destinationDirectoryName)
{
//Opens the zip file up to be read
using (ZipArchive archive = ZipFile.OpenRead(sourceArchiveFileName))
{
if (Directory.Exists(destinationDirectoryName)==false )
Directory.CreateDirectory(destinationDirectoryName);
//Loops through each file in the zip file
archive.ExtractToDirectory(destinationDirectoryName);
}
}
public void ExtractItems(string sourceArchiveFileName,List< string> _PathFilesinArchive, string destinationDirectoryName)
{
//Opens the zip file up to be read
using (ZipArchive archive = ZipFile.OpenRead(sourceArchiveFileName))
{
//Loops through each file in the zip file
foreach (ZipArchiveEntry file in archive.Entries)
{
int PosResult = _PathFilesinArchive.IndexOf(file.FullName);
if (PosResult != -1)
{
//Create Folder
if (Directory.Exists( destinationDirectoryName + "\\" +Path.GetDirectoryName( _PathFilesinArchive[PosResult])) == false)
Directory.CreateDirectory(destinationDirectoryName + "\\" + Path.GetDirectoryName(_PathFilesinArchive[PosResult]));
Stream OpenFileGetBytes = file.Open();
FileStream FileStreamOutput = new FileStream(destinationDirectoryName + "\\" + _PathFilesinArchive[PosResult], FileMode.Create);
byte[] ReadAllbytes = new byte[4096];//Capcity buffer
int ReadByte = 0; int TotalRead = 0;
while (TotalRead != file.Length)
{
//Read Bytes
ReadByte = OpenFileGetBytes.Read(ReadAllbytes, 0, ReadAllbytes.Length);
TotalRead += ReadByte;
//Write Bytes
FileStreamOutput.Write(ReadAllbytes, 0, ReadByte);
}
FileStreamOutput.Close();
OpenFileGetBytes.Close();
_PathFilesinArchive.RemoveAt(PosResult);
}
if (_PathFilesinArchive.Count == 0)
break;
}
}
}
public ZipItem[] ExtractItems(string sourceArchiveFileName)
{
List< ZipItem> ZipItemsReading = new List<ZipItem>();
//Opens the zip file up to be read
using (ZipArchive archive = ZipFile.OpenRead(sourceArchiveFileName))
{
//Loops through each file in the zip file
foreach (ZipArchiveEntry file in archive.Entries)
{
Stream OpenFileGetBytes = file.Open();
MemoryStream memstreams = new MemoryStream();
byte[] ReadAllbytes = new byte[4096];//Capcity buffer
int ReadByte = 0; int TotalRead = 0;
while (TotalRead != file.Length)
{
//Read Bytes
ReadByte = OpenFileGetBytes.Read(ReadAllbytes, 0, ReadAllbytes.Length);
TotalRead += ReadByte;
//Write Bytes
memstreams.Write(ReadAllbytes, 0, ReadByte);
}
memstreams.Position = 0;
OpenFileGetBytes.Close();
memstreams.Dispose();
ZipItemsReading.Add(new ZipItem(memstreams.ToArray(),file.FullName));
}
}
return ZipItemsReading.ToArray();
}
public ZipItem[] ExtractItems(string sourceArchiveFileName,List< string> _PathFilesinArchive)
{
List< ZipItem> ZipItemsReading = new List<ZipItem>();
//Opens the zip file up to be read
using (ZipArchive archive = ZipFile.OpenRead(sourceArchiveFileName))
{
//Loops through each file in the zip file
foreach (ZipArchiveEntry file in archive.Entries)
{
int PosResult = _PathFilesinArchive.IndexOf(file.FullName);
if (PosResult!= -1)
{
Stream OpenFileGetBytes = file.Open();
MemoryStream memstreams = new MemoryStream();
byte[] ReadAllbytes = new byte[4096];//Capcity buffer
int ReadByte = 0; int TotalRead = 0;
while (TotalRead != file.Length)
{
//Read Bytes
ReadByte = OpenFileGetBytes.Read(ReadAllbytes, 0, ReadAllbytes.Length);
TotalRead += ReadByte;
//Write Bytes
memstreams.Write(ReadAllbytes, 0, ReadByte);
}
//Create item
ZipItemsReading.Add(new ZipItem(memstreams.ToArray(),file.FullName));
OpenFileGetBytes.Close();
memstreams.Dispose();
_PathFilesinArchive.RemoveAt(PosResult);
}
if (_PathFilesinArchive.Count == 0)
break;
}
}
return ZipItemsReading.ToArray();
}

Trying To Gzip and Unzip but getting different content

I have the following functions to gzip and unzip text content, however the uncompressed output is not complete, missing approx the last 10th of the file (long html file). What am I doing wrong?
private byte[] GZipString(string input)
{
var bytes = Encoding.UTF8.GetBytes(input);
using (var mso = new MemoryStream())
using (var gz = new GZipStream(mso, CompressionMode.Compress))
{
gz.Write(bytes, 0, bytes.Length);
return mso.ToArray();
}
}
private string UnzipFile(string filename)
{
var bytes = File.ReadAllBytes(filename);
using (var msi = new MemoryStream(bytes))
using (var mso = new MemoryStream())
using (var gz = new GZipStream(msi, CompressionMode.Decompress))
{
gz.CopyTo(mso);
return Encoding.UTF8.GetString(mso.ToArray());
}
}

How to Download, Decompress and Deserialize an object/file from Azure Blob Storage?

This code will compress and serialize the object:
public static byte[] ObjectToByteArray(object[] obj)
{
using (MemoryStream msCompressed = new MemoryStream())
using (GZipStream gZipStream = new GZipStream(msCompressed, CompressionMode.Compress))
using (MemoryStream msDecompressed = new MemoryStream())
{
new BinaryFormatter().Serialize(msDecompressed, obj);
byte[] byteArray = msDecompressed.ToArray();
gZipStream.Write(byteArray, 0, byteArray.Length);
gZipStream.Close();
return msCompressed.ToArray();
}
}
And the following will upload it to the Azure Blob Storage:
byte[] byteObject = ObjectToByteArray(uploadObject);
using (Stream stream = new MemoryStream(byteObject))
{
stream.Seek(0, SeekOrigin.Begin);
blockBlob.UploadFromStream(stream, null, options);
}
This works great, but I can't find a way to download, decompress and deserialize this object/file from my storage.

You could use method DownloadToStream to download the file to local.
using (var fileStream = System.IO.File.OpenWrite(#"xxxx\compressedfile.gz"))
{
blockBlob.DownloadToStream(fileStream);
}
And then you could refer to the following code to decompress and deserialize the specified stream.
public static void DecompressAndDeserialize(string path)
{
using (FileStream originalFileStream = new FileStream(path, FileMode.Open, FileAccess.Read))
{
FileInfo fileToDecompress = new FileInfo(path);
string FileName = fileToDecompress.FullName;
string newFileName = FileName.Remove(FileName.Length - fileToDecompress.Extension.Length);
using (FileStream decompressedFileStream = File.Create(newFileName))
{
using (GZipStream decompressionStream = new GZipStream(originalFileStream, CompressionMode.Decompress))
{
decompressionStream.CopyTo(decompressedFileStream);
}
}
FileStream fs = new FileStream(newFileName, FileMode.Open);
BinaryFormatter formatter = new BinaryFormatter();
object[] uploadObject = (object[])formatter.Deserialize(fs);
}
}

Decompress byte array to string via BinaryReader yields empty string

I am trying to decompress a byte array and get it into a string using a binary reader. When the following code executes, the inStream position changes from 0 to the length of the array, but str is always an empty string.
BinaryReader br = null;
string str = String.Empty;
using (MemoryStream inStream = new MemoryStream(pByteArray))
{
GZipStream zipStream = new GZipStream(inStream, CompressionMode.Decompress);
BinaryReader br = new BinaryReader(zipStream);
str = br.ReadString();
inStream.Close();
br.Close();
}

You haven't shown how is the data being compressed, but here's a full example of compressing and decompressing a buffer:
using System;
using System.IO;
using System.IO.Compression;
using System.Text;
class Program
{
static void Main()
{
var test = "foo bar baz";
var compressed = Compress(Encoding.UTF8.GetBytes(test));
var decompressed = Decompress(compressed);
Console.WriteLine(Encoding.UTF8.GetString(decompressed));
}
static byte[] Compress(byte[] data)
{
using (var compressedStream = new MemoryStream())
using (var zipStream = new GZipStream(compressedStream, CompressionMode.Compress))
{
zipStream.Write(data, 0, data.Length);
zipStream.Close();
return compressedStream.ToArray();
}
}
static byte[] Decompress(byte[] data)
{
using (var compressedStream = new MemoryStream(data))
using (var zipStream = new GZipStream(compressedStream, CompressionMode.Decompress))
using (var resultStream = new MemoryStream())
{
zipStream.CopyTo(resultStream);
return resultStream.ToArray();
}
}
}