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How to get the stream response of my HttpResponseMessage in c#?

I am working with HttpClient and I want to get the stream response.
I want to make it work like Webresponse.getResponseStream() in order to read it in a BinaryReader like this :
BinaryReader reader = new BinaryReader(new BufferedStream(myWebResponse.GetResponseStream());
I have tried to use the GetStreamAsync, but it never works because I am forced to use await and the HttpResponseMessage gets bytes infinitely.
BinaryReader reader = new BinaryReader(new BufferedStream(await myHttpClient.GetStreamAsync());
I don't know how to use the CopyToAsync, so I don't know if it works..
Any idea ?
Edit : More details.
The method getStreamAsync works when I'm receiving one anwser, but since i'm receiving a live stream, I don't get the stream before the live ends !

NancyFx: Are streams disposed when using StreamResponse()?

Are streams disposed in NancyFx when using StreamResponse()?
Using a streamWriter to write to the stream, I can't dispose of it without closing the stream I want to send out. And the way I see it, I can't dispose of the stream manually either since I effectively left the method at the return.
This code works:
// Open a stream and write to it with streamReader
Stream memStream = new MemoryStream();
StreamWriter memWriter = new StreamWriter(memStream, Encoding.UTF8);
memWriter.Write(someStringText);
memWriter.Flush();
memStream.Position = 0;
// Add stream to the respose which should get downloaded
var response = new StreamResponse(() => memStream, MimeTypes.GetMimeType(contentType));
return response.AsAttachment(someFileName);
Do I need to worry about the stream lingering on until the garbage collector comes along or do it get disposed correctly by the StreamResponse?

According to StreamResponse.cs, StreamResponse.Dispose() disposes of the stream returned by the Func<Stream>, and Nancy handles disposing the Response at the end of the NancyContext.
As for disposing of StreamWriter without affecting the underlying stream, see this answer.

StreamReader and StreamWriter on the same Stream?

How do I manage closing StreamReader and StreamWriter which are using the same underlying stream?
var stream = /*...*/;
var reader = new StreamReader(stream);
var writer = new StreamWRiter(stream);
I know that I could simply ignore closing the reader/writer and just close the underlying stream. However, that seems a bit of a hack, since it is based on the assumption that the reader/writer doesn't have anything to dispose (which might not be the case in the future).
I know this have been solved in .NET 4.5 with an extra constructor argument, but until .NET 4.5 is released, how do I solve it in a proper way?

Make sure you Flush() the writer first.
And then just Dispose or Close the 2 decorators and the stream (nested usings are OK).

Why disposing StreamReader makes a stream unreadable? [duplicate]

This question already has answers here:
Can you keep a StreamReader from disposing the underlying stream?
(9 answers)
Closed 7 years ago.
I need to read a stream two times, from start to end.
But the following code throws an ObjectDisposedException: Cannot access a closed file exception.
string fileToReadPath = #"<path here>";
using (FileStream fs = new FileStream(fileToReadPath, FileMode.Open))
{
using (StreamReader reader = new StreamReader(fs))
{
string text = reader.ReadToEnd();
Console.WriteLine(text);
}
fs.Seek(0, SeekOrigin.Begin); // ObjectDisposedException thrown.
using (StreamReader reader = new StreamReader(fs))
{
string text = reader.ReadToEnd();
Console.WriteLine(text);
}
}
Why is it happening? What is really disposed? And why manipulating StreamReader affects the associated stream in this way? Isn't it logical to expect that a seekable stream can be read several times, including by several StreamReaders?

This happens because the StreamReader takes over 'ownership' of the stream. In other words, it makes itself responsible for closing the source stream. As soon as your program calls Dispose or Close (leaving the using statement scope in your case) then it will dispose the source stream as well. Calling fs.Dispose() in your case. So the file stream is dead after leaving the first using block. It is consistent behavior, all stream classes in .NET that wrap another stream behave this way.
There is one constructor for StreamReader that allows saying that it doesn't own the source stream. It is however not accessible from a .NET program, the constructor is internal.
In this particular case, you'd solve the problem by not using the using-statement for the StreamReader. That's however a fairly hairy implementation detail. There's surely a better solution available to you but the code is too synthetic to propose a real one.

The purpose of Dispose() is to clean up resources when you're finished with the stream. The reason the reader impacts the stream is because the reader is just filtering the stream, and so disposing the reader has no meaning except in the context of it chaining the call to the source stream as well.
To fix your code, just use one reader the entire time:
using (FileStream fs = new FileStream(fileToReadPath, FileMode.Open))
using (StreamReader reader = new StreamReader(fs))
{
string text = reader.ReadToEnd();
Console.WriteLine(text);
fs.Seek(0, SeekOrigin.Begin); // ObjectDisposedException not thrown now
text = reader.ReadToEnd();
Console.WriteLine(text);
}
Edited to address comments below:
In most situations, you do not need to access the underlying stream as you do in your code (fs.Seek). In these cases, the fact that StreamReader chains its call to the underlying stream allows you to economize on the code by not using a usings statement for the stream at all. For example, the code would look like:
using (StreamReader reader = new StreamReader(new FileStream(fileToReadPath, FileMode.Open)))
{
...
}

Using defines a scope, outside of which an object will be disposed, thus the ObjectDisposedException. You can't access the StreamReader's contents outside of this block.

I agree with your question. The biggest issue with this intentional side-effect is when developers don't know about it and are blindly following the "best practice" of surrounding a StreamReader with a using. But it can cause some really hard to track down bugs when it is on a long-lived object's property, the best (worst?) example I've seen is
using (var sr = new StreamReader(HttpContext.Current.Request.InputStream))
{
body = sr.ReadToEnd();
}
The developer had no idea the InputStream is now hosed for any future place that expects it to be there.
Obviously, once you know the internals you know to avoid the using and just read and reset the position. But I thought a core principle of API design was to avoid side effects, especially not destroying data you are acting upon. Nothing inherent about a class that supposedly is a "reader" should clear the data it reads when done "using" it. Disposing of the reader should release any references to the Stream, not clear the stream itself. The only thing I can think is that the choice had to be made since the reader is altering other internal state of the Stream, like the position of the seek pointer, that they assumed if you are wrapping a using around it you are intentionally going to be done with everything. On the other hand, just like in your example, if you are creating a Stream, the stream itself will be in a using, but if you are reading a Stream that was created outside of your immediate method, it is presumptuous of the code to clear the data.
What I do and tell our developers to do on Stream instances that the reading code doesn't explicitly create is...
// save position before reading
long position = theStream.Position;
theStream.Seek(0, SeekOrigin.Begin);
// DO NOT put this StreamReader in a using, StreamReader.Dispose() clears the stream
StreamReader sr = new StreamReader(theStream);
string content = sr.ReadToEnd();
theStream.Seek(position, SeekOrigin.Begin);
(sorry I added this as an answer, wouldn't fit in a comment, I would love more discussion about this design decision of the framework)

Dispose() on parent will Dispose() all owned streams. Unfortunately, streams don't have Detach() method, so you have to create some workaround here.

I don't know why, but you can leave your StreamReader undisposed. That way your underlying stream won't be disposed, even when StreamReader got collected.

C# File Exception: cannot access the file because it is being used by another process

I'm trying to download a file from the web and save it locally, but I get an exception:
C# The process cannot access the file
'blah' because it is being used by
another process.
This is my code:
File.Create("data.csv"); // create the file
request = (HttpWebRequest)WebRequest.CreateDefault(new Uri(url));
request.Timeout = 30000;
response = (HttpWebResponse)request.GetResponse();
using (Stream file = File.OpenWrite("data.csv"), // <-- Exception here
input = response.GetResponseStream())
{
// Save the file using Jon Skeet's CopyStream method
CopyStream(input, file);
}
I've seen numerous other questions with the same exception, but none of them seem to apply here. Any help?
Update:
Thanks for the answers! Removing the File.Create(...) fixed it!
One comment on the documentation of OpenWrite: it is a little misleading, the brief description says:
Opens an existing file for writing.
The detailed description says:
If the file exists, it is opened for
writing at the beginning. The existing
file is not truncated.
Update 2.0:
It looks like the discrepancy is between IntelliSense/F1 and the online documentation. I thought it should be the same since I allow F1 to connect to the web when it's displaying documentation.

File.Create returns a FileStream - which you're not closing. That means you won't be able to open another stream writing to the same file until the finalizer has closed the existing stream.
Just get rid of the call to File.Create - File.OpenWrite will create it anyway. Alternatively, keep the FileStream around to write to:
using (Stream file = File.Create("data.csv"))
{
request = (HttpWebRequest)WebRequest.CreateDefault(new Uri(url));
request.Timeout = 30000;
using (var response = (HttpWebResponse)request.GetResponse())
using (Stream input = response.GetResponseStream())
{
// Save the file using Jon Skeet's CopyStream method
CopyStream(input, file);
}
}
Note that I'm also disposing of the WebResponse here, which you should do to make sure the connection is freed to the connection pool.

looks like File.Create returns an open FileStream object
http://msdn.microsoft.com/en-us/library/aa328775(v=VS.71).aspx
try
using (FileStream fs = File.Create("data.csv"))
and leave off the first File.Create

The problem is that the File.Create method actually opens the file and returns a FileStream object. It won't close the file until the object is garbage collected (which will happen at an indeterminate time). The FileStream object still gets created, regardless of whether or not you use it. Try this:
using (Stream file = File.Create("data.csv"),
input = response.GetResponseStream())
{
// Save the file using Jon Skeet's CopyStream method
CopyStream(input, file);
}

First. File.Create will return a stream that you should use for accessing the file.
Second, if that doesn't resolve the issue, if you google who lock you will find a program that let's you determine what process is accessing a file at the same time.