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How to get the contentByte for the file that is uploaded by user C#

I am working on ASP.Net MVC 4.7 project, in which I am using Microsoft graph api to send mail.
I want to know what is the contentByte. How I can get it from the filestream. See the following code. I am searching for
fileAttachment.ContentBytes=
Note that files are in stream they are uploaded by the user.
private static MessageAttachmentsCollectionPage GetAttachments(List<HttpPostedFileBase> fileUploader)
{
var attachmentPage = new MessageAttachmentsCollectionPage();
if (fileUploader != null)
{
foreach (var file in fileUploader)
{
var fileAttachment = new FileAttachment();
fileAttachment.Name = file.FileName;
fileAttachment.ContentType = file.ContentType;
fileAttachment.ContentBytes = ??
attachmentPage.Add(fileAttachment);
}
}

This is just a base64-encoded contents of the file (string). For example:
public static class StreamExtensions
{
public static string ConvertToBase64(this Stream stream)
{
if (stream is MemoryStream memoryStream)
{
return Convert.ToBase64String(memoryStream.ToArray());
}
var bytes = new Byte[(int)stream.Length];
stream.Seek(0, SeekOrigin.Begin);
stream.Read(bytes, 0, (int)stream.Length);
return Convert.ToBase64String(bytes);
}
}
You may find different approaches described in the Encode a FileStream to base64 with c# thread.

Web service File Stream to Byte[] to FileStream to pdf failing C#

I am trying to create a web service that returns a pdf file as a byte[] and then the app that consumes it grabs the byte[] and saves it as a pdf file and then opens it. The file fails to open at the end.
Here is the Web Service that returns a byte[]
[WebMethod]
public byte[] XXXX(int fileID)
{
try
{
using (EntitiesModel dbContext = new EntitiesModel())
{
string fileFullPath = .....
.......
if (fileFullNamePath != null)
{
FileStream fileStream = new FileStream(fileFullNamePath, FileMode.Open, System.IO.FileAccess.Read);
int len = fileStream.Length.ToInt();
Byte[] documentContents = new byte[len];
fileStream.Read(documentContents, 0, len);
fileStream.Close();
return documentContents;
Then it is called from an app with the following code
string soap = "<?xml version=\"1.0\" encoding=\"utf - 8\"?>" +
"<soap:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">" +
"<soap:Body>" +
"<XXXX xmlns=\"http://tempuri.org/\">" +
"<fileID>XXXXX</fileID>" +
"</XXXX>" +
"</soap:Body>" +
"</soap:Envelope>";
string localhostContext = #"http://localhost:3381/";
string webserviceAddress = #"XXXX/XXXX/XXXXX.asmx";
string url = localhostContext + webserviceAddress ;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.ContentType = "text/xml";
request.ContentLength = soap.Length;
request.Timeout = 20000;
request.Method = "POST";
using (Stream stream = request.GetRequestStream())
{
using (StreamWriter streamWriter = new StreamWriter(stream))
{
streamWriter.Write(soap); }
}
}
byte[] bytes;
try
{
WebResponse response = request.GetResponse();
bytes = ReadFully(response.GetResponseStream());
}
catch (Exception exception)
{
throw;
}
private byte[] ReadFully(Stream input)
{
byte[] buffer = new byte[16*1024];
using (MemoryStream memoryStream = new MemoryStream())
{
int read;
while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
{
memoryStream.Position = 0;
memoryStream.Write(buffer, 0, read);
}
return memoryStream.ToArray();
}
}
FileStream objfilestream =
new FileStream(fileName, FileMode.Create,FileAccess.ReadWrite);
objfilestream.Write(bytes, 0, bytes.Length);
objfilestream.Close();
var process = Process.Start(fileName);
The code runs fine and creates a pdf and then tries to open that pdf. But the file can not be opened. Adobe Acrobat gives the error
Adobe Acrobat Reader could not open XXX.pdf because it is either not a
supported file type or because the file has been damaged (for example, it
was sent as an email attachment and wasn't correctly decoded).
Because I am not getting an error in the code I am at a loss to know where the error is that is not creating the proper file.
There was an issue with the Stream variable called input was not giving length so I used Jon Skeet's suggestion here Stackoverflow:Creating a byte array from a stream
new byte[16*1024];
rather than
new byte[input.length]

There were three things wrong.
memoryStream.Position = 0;
in the while loop was problematic so I removed it.
Secondly when reading the stream. What it returned was the SOAP XMl message with the encoded base64 string in the the XXXXResult XML tag. So I had to extract that.
Finally I had to use
byte[] fileResultBytes = Convert.FromBase64String(resultString);
to get the byte[] from the resultString extracted from the SOAP message. In the test SOAP message, that can be generated locally, it tells you the type of this result string. I missed that initially.
Thanks to VC.One and CodeCaster for their correct suggestions.

Save a zip file to memory and unzip file from stream and get content

I am currently working on integrating Amazon Prime on our system and being stuck at getting the label back as ZPL format.
Basically, Amazon returns a base64 string, we will need to convert that string to a byte array, then save that array as a *.gzip file. From that gzip file, we can extract the content and get the zpl label content.
My question is, how we can do all of above without storing any temp files to system. I have researched some solutions but none is working for me.
My current code as below:
var str = "base64string";
var label = Convert.FromBase64String(str);
using (var memoryStream = new MemoryStream())
{
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
{
var demoFile = archive.CreateEntry("label.zip");
var entryStream = demoFile.Open();
using (var bw = new BinaryWriter(entryStream))
{
bw.Write(label);
}
var data = new MemoryStream();
using (var zip = ZipFile.Read(entryStream))
{
zip["label"].Extract(data);
}
data.Seek(0, SeekOrigin.Begin);
entryStream.Close();
}
using (var fileStream = new FileStream(#"D:\test.zip", FileMode.Create))
{
memoryStream.Seek(0, SeekOrigin.Begin);
memoryStream.CopyTo(fileStream);
}
}
If I save the file as test.zip, I can successfully get the label back. But if I try to extract it directly to another stream, I get an error
A stream from ZipArchiveEntry has been disposed

I've done something similar, taking PNG label data from a zipped web response. This is how I went about that
using (WebClient webClient = new WebClient())
{
// Download. Expect this to be a zip file
byte[] data = webClient.DownloadData(urlString);
MemoryStream memoryStream = new MemoryStream(data);
ZipArchive zipArchive = new ZipArchive(memoryStream);
foreach (var zipEntry in zipArchive.Entries)
{
// Can check file name here and ignore anything in zip we're not expecting
if (!zipEntry.Name.EndsWith(".png")) continue;
// Open zip entry as stream
Stream extractedFile = zipEntry.Open();
// Convert stream to memory stream
MemoryStream extractedMemoryStream = new MemoryStream();
extractedFile.CopyTo(extractedMemoryStream);
// At this point the extractedMemoryStream is a sequence of bytes containing image data.
// In this test project I'm pushing that into a bitmap image, just to see something on screen, but could as easily be written to a file or passed for storage to sql or whatever.
BitmapDecoder decoder = PngBitmapDecoder.Create(extractedMemoryStream, BitmapCreateOptions.None, BitmapCacheOption.OnLoad);
BitmapFrame frame = decoder.Frames.First();
frame.Freeze();
this.LabelImage.Source = frame;
}
}

I was overthinking it. I finally found a simple way to do it. We just need to convert that base64 string to bytes array and use GzipStream to directly decompress it. I leave the solution here in case someone needs it. Thanks!
var label = Convert.FromBase64String(str);
using (var compressedStream = new MemoryStream(label))
using (var zipStream = new GZipStream(compressedStream, CompressionMode.Decompress))
using (var resultStream = new MemoryStream())
{
zipStream.CopyTo(resultStream);
return resultStream.ToArray();
}

ICSharpZipLib - unziping file issue

I have an application in ASP.NET where user can upload ZIP file. I'm trying to extract file using ICSharpZipLib (I also tried DotNetZip, but had same issue).
This zip file contains single xml document (9KB before compress).
When I open this file with other applications on my desktop (7zip, windows explorer) it seems to be ok.
My unzip method throws System.OutOfMemoryException and I have no idea why is that. When I debugged my unziping method I noticed that zipInputStreams' Length property throws Exception and is not available:
Stream UnZipSingleFile(Stream memoryStream)
{
var zipInputStream = new ZipInputStream(memoryStream);
memoryStream.Position = 0;
zipInputStream.GetNextEntry();
MemoryStream unzippedStream = new MemoryStream();
int len;
byte[] buf = new byte[4096];
while ((len = zipInputStream.Read(buf, 0, buf.Length)) > 0)
{
unzippedStream.Write(buf, 0, len);
}
unzippedStream.Position = 0;
memoryStream.Position = 0;
return unzippedStream;
}
and here's how I get string of unzippedStream:
string GetString()
{
var reader = new StreamReader(unzippedStream);
var result = reader.ReadToEnd();
unzippedStream.Position = 0;
return result;
}

From their wiki:
"Sharpzip supports Zip files using both stored and deflate compression methods and also supports old (PKZIP 2.0) style and AES encryption"
Are you sure the format of the uploaded zip file is acceptable for SharpZipLib?

While this post is quite old, I think it could be beneficial to illustrate how I did this for compression and decompression using ICSharpZipLib (C# package version 1.1.0). I put this together by looking into the examples shown here (see ie. these compression and decompression examples).
Assumption: The input to the compression and decompression below should be in bytes. If you have ie. an xml file you could load it to an XDocument, and convert it into an XmlDocument with .ToXmlDocument(). From there, you could access the string contents by calling .OuterXml, and converting the string to a byte array.
// Compression (inputBytes = ie. string-to-compress, as bytes)
using var dataStream = new MemoryStream(inputBytes);
var outputStream = new MemoryStream();
using (var zipStream = new ZipOutputStream(outputStream))
{
zipStream.SetLevel(3);
var newEntry = new ZipEntry("someFilename.someExtension");
newEntry.DateTime = DateTime.Now;
zipStream.PutNextEntry(newEntry);
StreamUtils.Copy(dataStream, zipStream, new byte[4096]);
zipStream.CloseEntry();
zipStream.IsStreamOwner = false;
}
outputStream.Position = 0;
var outputBytes = outputStream.ToArray();
// Decompression (inputBytes = ie. string-to-decompress, as bytes)
using var dataStream = new MemoryStream(inputBytes);
var outputStream = new MemoryStream();
using (var zipStream = new ZipInputStream(dataStream))
{
while (zipStream.GetNextEntry() is ZipEntry zipEntry)
{
var buffer = new byte[4096];
StreamUtils.Copy(zipStream, outputStream, buffer);
}
}
var outputBytes = outputStream.ToArray();

How to use WebResponse to Download .wmv file

I'm using the following code to grab a wmv file through a WebResponse. I'm using a thread to call this function:
static void GetPage(object data)
{
// Cast the object to a ThreadInfo
ThreadInfo ti = (ThreadInfo)data;
// Request the URL
WebResponse wr = WebRequest.Create(ti.url).GetResponse();
// Display the value for the Content-Length header
Console.WriteLine(ti.url + ": " + wr.Headers["Content-Length"]);
string toBeSaved = #"C:\Users\Kevin\Downloads\TempFiles" + wr.ResponseUri.PathAndQuery;
StreamWriter streamWriter = new StreamWriter(toBeSaved);
MemoryStream m = new MemoryStream();
Stream receiveStream = wr.GetResponseStream();
using (StreamReader sr = new StreamReader(receiveStream))
{
while (sr.Peek() >= 0)
{
m.WriteByte((byte)sr.Read());
}
streamWriter.Write(sr.ReadToEnd());
sr.Close();
wr.Close();
}
streamWriter.Flush();
streamWriter.Close();
// streamReader.Close();
// Let the parent thread know the process is done
ti.are.Set();
wr.Close();
}
The file seems to download just fine, but Windows Media Viewer cannot open the file properly. Some silly error about not being able to support the file type.
What incredibly easy thing am I missing?

You just need to download it as binary instead of text. Here's a method that should do the trick for you.
public void DownloadFile(string url, string toLocalPath)
{
byte[] result = null;
byte[] buffer = new byte[4097];
WebRequest wr = WebRequest.Create(url);
WebResponse response = wr.GetResponse();
Stream responseStream = response.GetResponseStream;
MemoryStream memoryStream = new MemoryStream();
int count = 0;
do {
count = responseStream.Read(buffer, 0, buffer.Length);
memoryStream.Write(buffer, 0, count);
if (count == 0) {
break;
}
}
while (true);
result = memoryStream.ToArray;
FileStream fs = new FileStream(toLocalPath, FileMode.OpenOrCreate, FileAccess.ReadWrite);
fs.Write(result, 0, result.Length);
fs.Close();
memoryStream.Close();
responseStream.Close();
}

I do not understand why you are filling MemoryStream m one byte at a time, but then writing the sr to the file. At that point, I believe the sr is empty, and MemoryStream m is never used.
Below is some code I wrote to do a similar task. It gets a WebResponse in 32K chunks at a time, and dumps it directly to a file.
public void GetStream()
{
// ASSUME: String URL is set to a valid URL.
// ASSUME: String Storage is set to valid filename.
Stream response = WebRequest.Create(URL).GetResponse().GetResponseStream();
using (FileStream fs = File.Create(Storage))
{
Byte[] buffer = new Byte[32*1024];
int read = response.Read(buffer,0,buffer.Length);
while (read > 0)
{
fs.Write(buffer,0,read);
read = response.Read(buffer,0,buffer.Length);
}
}
// NOTE: Various Flush and Close of streams and storage not shown here.
}

You are using a StreamReader and a StreamWriter to transfer your stream, but those classes are for handling text. Your file is binary and chances are that sequences of CR, LF and CR LF may get clobbered when you transfer the data. How NUL characters are handled I have no idea.