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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.

Save a HTTP stream to file in c#

Im getting a XML-response as a HTTPresponse, that works well. Now im trying to save it to disc for future usage as well. Im trying to use the second method described in How do I save a stream to a file in C#? (did not get the first method to work either). The file is created but empty
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
XmlDocument events = new XmlDocument();
events.Load(reader);
var fileStream = File.Create("C:\\XMLfiles\\test.xml");
CopyStream(dataStream, fileStream);
fileStream.Close();
public static void CopyStream(Stream input, Stream output)
{
byte[] buffer = new byte[8 * 1024];
int len;
while ((len = input.Read(buffer, 0, buffer.Length)) > 0)
{
output.Write(buffer, 0, len);
}
}

Please use following code snippet. Don't forget about "using" approach!
HttpWebRequest tt = HttpWebRequest.CreateHttp("http://www.stackoverflow.com");
using (var yy = tt.GetResponse())
using (var stream = yy.GetResponseStream())
using (var file = File.Open(#"c:\response.html", FileMode.Create))
{
stream.CopyTo(file);
stream.Flush();
}

This is a tricky situation. The problem is you read the HttpResponseStream already. As a result, you're at the end of the stream. Under normal circumstances you'd just set dataStream.Position = 0. However, you can't do that here because we're not talking about a file on your PC, it's a network stream so you can't "go backwards" (it was already sent to you). As a result, what I'd recommend you do is instead of trying to write the original stream again, write your XmlDocument.
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
XmlDocument events = new XmlDocument();
events.Load(reader);
events.Save("C:\\XMLfiles\\test.xml");
In that case it will work since you're saving the data that's been copied to the XmlDocument rather than trying to reread a network stream.

Convert to Stream from a Url

I was trying to convert an Url to Stream but I am not sure whether I am right or wrong.
protected Stream GetStream(String gazouUrl)
{
Stream rtn = null;
HttpWebRequest aRequest = (HttpWebRequest)WebRequest.Create(gazouUrl);
HttpWebResponse aResponse = (HttpWebResponse)aRequest.GetResponse();
using (StreamReader sReader = new StreamReader(aResponse.GetResponseStream(), System.Text.Encoding.Default))
{
rtn = sReader.BaseStream;
}
return rtn;
}
Am I on the right track?

I ended up doing a smaller version and using WebClient instead the old Http Request code:
private static Stream GetStreamFromUrl(string url)
{
byte[] imageData = null;
using (var wc = new System.Net.WebClient())
imageData = wc.DownloadData(url);
return new MemoryStream(imageData);
}

You don't need to create a StreamReader there. Just return aResponse.GetResponseStream();. The caller of that method will also need to call Dispose on the stream when it's done.

The current answer is missing an example in how to use GetResponseStream()
Here is an example
// Creates an HttpWebRequest with the specified URL.
HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(url);
// Sends the HttpWebRequest and waits for the response.
HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();
// Gets the stream associated with the response.
Stream receiveStream = myHttpWebResponse.GetResponseStream();
Encoding encode = System.Text.Encoding.GetEncoding("utf-8");
// Pipes the stream to a higher level stream reader with the required encoding format.
StreamReader readStream = new StreamReader( receiveStream, encode );
Console.WriteLine("\r\nResponse stream received.");
Char[] read = new Char[256];
// Reads 256 characters at a time.
int count = readStream.Read( read, 0, 256 );
Console.WriteLine("HTML...\r\n");
while (count > 0)
{
// Dumps the 256 characters on a string and displays the string to the console.
String str = new String(read, 0, count);
Console.Write(str);
count = readStream.Read(read, 0, 256);
}
Console.WriteLine("");
// Releases the resources of the response.
myHttpWebResponse.Close();
// Releases the resources of the Stream.
readStream.Close();
For more details see - https://learn.microsoft.com/en-us/dotnet/api/system.net.httpwebresponse.getresponsestream?view=net-5.0

FtpWebRequest Download File Incorrect Size

I’m using the following code to download a file from a remote ftp server:
FtpWebRequest request = (FtpWebRequest)WebRequest.Create(serverPath);
request.KeepAlive = true;
request.UsePassive = true;
request.UseBinary = true;
request.Method = WebRequestMethods.Ftp.DownloadFile;
request.Credentials = new NetworkCredential(userName, password);
using (FtpWebResponse response = (FtpWebResponse)request.GetResponse())
using (Stream responseStream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(responseStream))
using (StreamWriter destination = new StreamWriter(destinationFile))
{
destination.Write(reader.ReadToEnd());
destination.Flush();
}
The file that I’m downloading is a dll and my problem is that it is being altered by this process in some way. I know this because the file size is increasing. I have a suspicion that this section of code is at fault:
destination.Write(reader.ReadToEnd());
destination.Flush();
Can anyone offer any ideas as to what may be wrong?

StreamReader and StreamWriter work with character data, so you are decoding the stream from bytes to characters and then encoding it back to bytes again. A dll file contains binary data, so this round-trip conversion will introduce errors. You want to read bytes directly from the responseStream object and write to a FileStream that isn't wrapped in a StreamWriter.
If you are using .NET 4.0 you can use Stream.CopyTo, but otherwise you will have to copy the stream manually. This StackOverflow question has a good method for copying streams:
public static void CopyStream(Stream input, Stream output)
{
byte[] buffer = new byte[32768];
while (true)
{
int read = input.Read(buffer, 0, buffer.Length);
if (read <= 0)
return;
output.Write(buffer, 0, read);
}
}
So, your code will look like this:
using (FtpWebResponse response = (FtpWebResponse)request.GetResponse())
using (Stream responseStream = response.GetResponseStream())
using (FileStream destination = File.Create(destinationFile))
{
CopyStream(responseStream, destination);
}

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.