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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.

Read Http Request into Byte array

I'm developing a web page that needs to take an HTTP Post Request and read it into a byte array for further processing. I'm kind of stuck on how to do this, and I'm stumped on what is the best way to accomplish. Here is my code so far:
public override void ProcessRequest(HttpContext curContext)
{
if (curContext != null)
{
int totalBytes = curContext.Request.TotalBytes;
string encoding = curContext.Request.ContentEncoding.ToString();
int reqLength = curContext.Request.ContentLength;
long inputLength = curContext.Request.InputStream.Length;
Stream str = curContext.Request.InputStream;
}
}
I'm checking the length of the request and its total bytes which equals 128. Now do I just need to use a Stream object to get it into byte[] format? Am I going in the right direction? Not sure how to proceed. Any advice would be great. I need to get the entire HTTP request into byte[] field.
Thanks!

The simplest way is to copy it to a MemoryStream - then call ToArray if you need to.
If you're using .NET 4, that's really easy:
MemoryStream ms = new MemoryStream();
curContext.Request.InputStream.CopyTo(ms);
// If you need it...
byte[] data = ms.ToArray();
EDIT: If you're not using .NET 4, you can create your own implementation of CopyTo. Here's a version which acts as an extension method:
public static void CopyTo(this Stream source, Stream destination)
{
// TODO: Argument validation
byte[] buffer = new byte[16384]; // For example...
int bytesRead;
while ((bytesRead = source.Read(buffer, 0, buffer.Length)) > 0)
{
destination.Write(buffer, 0, bytesRead);
}
}

You can just use WebClient for that...
WebClient c = new WebClient();
byte [] responseData = c.DownloadData(..)
Where .. is the URL address for the data.

I use MemoryStream and Response.GetResponseStream().CopyTo(stream)
HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(url);
myRequest.Method = "GET";
WebResponse myResponse = myRequest.GetResponse();
MemoryStream ms = new MemoryStream();
myResponse.GetResponseStream().CopyTo(ms);
byte[] data = ms.ToArray();

I have a function that does it, by sending in the response stream:
private byte[] ReadFully(Stream input)
{
try
{
int bytesBuffer = 1024;
byte[] buffer = new byte[bytesBuffer];
using (MemoryStream ms = new MemoryStream())
{
int readBytes;
while ((readBytes = input.Read(buffer, 0, buffer.Length)) > 0)
{
ms.Write(buffer, 0, readBytes);
}
return ms.ToArray();
}
}
catch (Exception ex)
{
// Exception handling here: Response.Write("Ex.: " + ex.Message);
}
}
Since you have Stream str = curContext.Request.InputStream;, you could then just do:
byte[] bytes = ReadFully(str);
If you had done this:
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(someUri);
req.Credentials = CredentialCache.DefaultCredentials;
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
You would call it this way:
byte[] bytes = ReadFully(resp.GetResponseStream());

class WebFetch
{
static void Main(string[] args)
{
// used to build entire input
StringBuilder sb = new StringBuilder();
// used on each read operation
byte[] buf = new byte[8192];
// prepare the web page we will be asking for
HttpWebRequest request = (HttpWebRequest)
WebRequest.Create(#"http://www.google.com/search?q=google");
// execute the request
HttpWebResponse response = (HttpWebResponse)
request.GetResponse();
// we will read data via the response stream
Stream resStream = response.GetResponseStream();
string tempString = null;
int count = 0;
do
{
// fill the buffer with data
count = resStream.Read(buf, 0, buf.Length);
// make sure we read some data
if (count != 0)
{
// translate from bytes to ASCII text
tempString = Encoding.ASCII.GetString(buf, 0, count);
// continue building the string
sb.Append(tempString);
}
}
while (count > 0); // any more data to read?
// print out page source
Console.WriteLine(sb.ToString());
Console.Read();
}
}

For all those cases when your context.Request.ContentLength is greather than zero, you can simply do:
byte[] contentBytes = context.Request.BinaryRead(context.Request.ContentLength);

using http response how to save the pdf files

I've written following code to get the content from a web page and save to the system.
if the webpage is in html format i'm able to save it.
if the web page is in pdf format i'm unable to save it. After saving if i opend the file blank pages are coming.
I want to know How to save the pdf files from the response.
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(Url);
WebResponse response = request.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader reader = new StreamReader(stream);
webContent = reader.ReadToEnd();
StreamWriter sw = new StreamWriter(FileName);
sw.WriteLine(webContent);
sw.Close();
Please help me ASAP.

StreamReader.ReadToEnd() returns a string. PDF files are binary, and contain data that is not string-friendly. You need to read it into a byte array, and write the byte array to disk. Even better, use a smaller byte array as a buffer and read in small chunks.
You can also simplify the whole thing by just using webclient:
using (var wc = new System.Net.WebClient())
{
wc.DownloadFile(Url, FileName);
}

HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(Url);
WebResponse response = request.GetResponse();
using (Stream stream = response.GetResponseStream())
using (FileStream fs = new FileStream(FileName, FileMode.Create, FileAccess.Write, FileShare.None))
{
stream.BlockCopy(fs);
}
...
public static class StreamHelper
{
public static void Copy(Stream source, Stream target, int blockSize)
{
int read;
byte[] buffer = new byte[blockSize];
while ((read = source.Read(buffer, 0, blockSize)) > 0)
{
target.Write(buffer, 0, read);
}
}
public static void BlockCopy(this Stream source, Stream target, int blockSize = 65536)
{
Copy(source, target, blockSize);
}
}

How to compress a HttpWebRequest POST

I am trying to post data to server that accepts compressed data. The code below works just fine, but it is uncompressed. I have not worked with compression or Gzip beofre, so any help is appriciated.
HttpWebRequest request = WebRequest.Create(uri) as HttpWebRequest;
request.Timeout = 600000;
request.Method = verb; // POST
request.Accept = "text/xml";
if (!string.IsNullOrEmpty(data))
{
request.ContentType = "text/xml";
byte[] byteData = UTF8Encoding.UTF8.GetBytes(data);
request.ContentLength = byteData.Length;
// Here is where I need to compress the above byte array using GZipStream
using (Stream postStream = request.GetRequestStream())
{
postStream.Write(byteData, 0, byteData.Length);
}
}
XmlDocument xmlDoc = new XmlDocument();
HttpWebResponse response = null;
StreamReader reader = null;
try
{
response = request.GetResponse() as HttpWebResponse;
reader = new StreamReader(response.GetResponseStream());
xmlDoc.LoadXml(reader.ReadToEnd());
}
Do I gzip the entire byte array? Do I need to add other headers or remove the one that is already there?
Thanks!
-Scott

To answer the question you asked, to POST compressed data, all you need to do is wrap the request stream with a gzip stream
using (Stream postStream = request.GetRequestStream())
{
using(var zipStream = new GZipStream(postStream, CompressionMode.Compress))
{
zipStream.Write(byteData, 0, byteData.Length);
}
}
This is completely different than requesting a gzip response, which is a much more common thing to do.

I also received the "Cannot close stream until all bytes are written" error using code similar to tnyfst's. The problem was that I had:
request.ContentLength = binData.Length;
where binData is my raw data before the compression. Obviously the length of the compressed content would be different, so I just removed this line and ended up with this code:
using (GZipStream zipStream = new GZipStream(request.GetRequestStream(), CompressionMode.Compress))
{
zipStream.Write(binData, 0, binData.Length);
}

In Page_Load event:
Response.AddHeader("Content-Encoding", "gzip");
And for making compressed requests:
HttpWebRequest and GZip Http Responses by Rick Strahl

Try this extension method.
The stream will be left open (see the GZipStream constructor).
The stream position is set to 0 after the compression is done.
public static void GZip(this Stream stream, byte[] data)
{
using (var zipStream = new GZipStream(stream, CompressionMode.Compress, true))
{
zipStream.Write(data, 0, data.Length);
}
stream.Position = 0;
}
You can use the following test:
[Test]
public void Test_gzip_data_is_restored_to_the_original_value()
{
var stream = new MemoryStream();
var data = new byte[]{1,2,3,4,5,6,7,8,9,10};
stream.GZip(data);
var decompressed = new GZipStream(stream, CompressionMode.Decompress);
var data2 = new byte[10];
decompressed.Read(data2,0,10);
Assert.That(data, Is.EqualTo(data2));
}
For more information see: http://msdn.microsoft.com/en-us/library/hh158301(v=vs.110).aspx

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.