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Getting JSON data from a response stream and reading it as a string?

I am trying to read a response from a server that I receive when I send a POST request. Viewing fiddler, it says it is a JSON response. How do I decode it to a normal string using C# Winforms with preferably no outside APIs. I can provide additional code/fiddler results if you need them.
The fiddler and gibberish images:
The gibberish came from my attempts to read the stream in the code below:
Stream sw = requirejs.GetRequestStream();
sw.Write(logBytes, 0, logBytes.Length);
sw.Close();
response = (HttpWebResponse)requirejs.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader sr = new StreamReader(stream);
MessageBox.Show(sr.ReadToEnd());

As mentioned in the comments, Newtonsoft.Json is really a good library and worth using -- very lightweight.
If you really want to only use Microsoft's .NET libraries, also consider System.Web.Script.Serialization.JavaScriptSerializer.
var serializer = new System.Web.Script.Serialization.JavaScriptSerializer();
var jsonObject = serializer.DeserializeObject(sr.ReadToEnd());

Going to assume (you haven't clarified yet) that you need to actually decode the stream, since A) retrieving a remote stream of text is well documented, and B) you can't do anything much with a non-decoded JSON stream.
Your best course of action is to implement System.Web.Helpers.Json:
using System.Web.Helpers.Json
...
var jsonObj = Json.Decode(jsonStream);

Reading information from a website c#

In the project I have in mind I want to be able to look at a website, retrieve text from that website, and do something with that information later.
My question is what is the best way to retrieve the data(text) from the website. I am unsure about how to do this when dealing with a static page vs dealing with a dynamic page.
From some searching I found this:
WebRequest request = WebRequest.Create("anysite.com");
// If required by the server, set the credentials.
request.Credentials = CredentialCache.DefaultCredentials;
// Get the response.
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
// Display the status.
Console.WriteLine(response.StatusDescription);
Console.WriteLine();
// Get the stream containing content returned by the server.
using (Stream dataStream = response.GetResponseStream())
{
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream, Encoding.UTF8);
// Read the content.
string responseString = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseString);
reader.Close();
}
response.Close();
So from running this on my own I can see it returns the html code from a website, not exactly what I'm looking for. I eventually want to be able to type in a site (such as a news article), and return the contents of the article. Is this possible in c# or Java?
Thanks

I hate to brake this to you but that's how webpages looks, it's a long stream of html markup/content. This gets rendered by the browser as what you see on your screen. The only way I can think of is to parse to html by yourself.
After a quick search on google I found this stack overflow article.
What is the best way to parse html in C#?
but I'm betting you figured this would be a bit easier than you expected, but that's the fun in programming always challenging problems

You can just use a WebClient:
using(var webClient = new WebClient())
{
string htmlFromPage = webClient.DownloadString("http://myurl.com");
}
In the above example htmlFromPage will contain the HTML which you can then parse to find the data you're looking for.

What you are describing is called web scraping, and there are plenty of libraries that do just that for both Java and C#. It doesn't really matter if the target site is static or dynamic since both output HTML in the end. JavaScript or Flash heavy sites on the other hand tend to be problematic.

Please try this,
System.Net.WebClient wc = new System.Net.WebClient();
string webData = wc.DownloadString("anysite.com");

Proper way of reading from a HttpWebResponse and .NET 4.0 Framework

We are currently experiencing a problem reading a ResponseStream that we have had no issues with in the past. Since adding .NET 4.0 Framwework to our server last night and assigning IIS to use the new framework we are experiencing a few different exceptions when trying to read the responseStream using the following statement (responseStream = httpResponse.GetResponseStream();). Everything up to that point works completely fine. So, I am looking for changes/improvements on how to read from the response. I have pasted the code below that we are using and the exceptions we are experiencing.
Our environment is:
.NET Framework 4.0
Windows Server 2003
THE CODE:
HttpWebResponse httpResponse;
Stream responseStream;
//Accept All Certificate Policy
ServicePointManager.ServerCertificateValidationCallback += delegate { return true; };
HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(new Uri(theUrl));
httpRequest.Method = "POST";
httpRequest.KeepAlive = false;
httpRequest.Timeout = timeOut;
try
{
httpResponse = (HttpWebResponse)httpRequest.GetResponse();
responseStream = httpResponse.GetResponseStream();
}
THE EXCEPTIONS:
'httpResponse.GetResponseStream().Length' threw an exception of type 'System.NotSupportedException' long {System.NotSupportedException}
'httpResponse.GetResponseStream().Position' threw an exception of type 'System.NotSupportedException' long {System.NotSupportedException}
{"This stream does not support seek operations."} System.SystemException {System.NotSupportedException}
Regards,
Mike

You haven't shown the bit of code which tries to use the length - but basically, you aren't guaranteed that you'll know the length of the stream. The server may not have given a content-length header.
If you need to mess with the stream, it's probably best to just copy all the data into a MemoryStream. With .NET 4, that's really easy:
MemoryStream ms = new MemoryStream();
responseStream.CopyTo(ms);
If you don't actually need the length for anything (e.g. you just want to load the results as an XML document) then just read from the stream without calling Length.
Note that it's generally good practice to declare variables at the point of initialization if possible - and you should use using statements for the web response and the response stream.

Download a file from the internet?

How can I easily download a file from internet in C#?
Thank you very much.

WebClient.DownloadFIle is one simple way.

Have a look at the BCL class System.Net.WebRequest. Here's a brief example:
using System.Net;
...
var request = WebRequest.Create(new Uri("http://..."));
var response = request.GetResponse();
var responseStream = response.GetResponseStream();
// ^^^^^^^^^^^^^^
// read web resource content through this stream object!
...
Take note:
Some of these objects are IDisposable, so in real code you might want to wrap them in using blocks.
The above code example does not do any error checking. You might want to add appropriate code for this, also.

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.