Develop Reference

WebClient.DownloadString uses wrong encoding

I'm downloading XML files from sharepoint online using webclient.
However, when I use WebClient.DownloadString(string url) method, some characters are not correctly decoded.
When I use WebClient.DownloadFile(string url, string file) and then I read the file all characters are correct.
The xml itself does not contain encoding declaration.
string wrongXml = webClient.DownloadString(url);
//wrongXml contains Ä™ instead of ę
webClient.DownloadFile(url, #"C:\temp\file1.xml");
string correctXml = File.ReadAllText(#"C:\temp\file1.xml");
//contains ę, like it should.
Also, when open the url in Internet Explorer, it is shown correctly.
Why is that? Is it because of the default windows encoding on my machine or webclient handles responses differently when using DownloadString, resp DownloadFile?

Probably the encoding it is using now is not the one the service returns.
You can set the encoding you expect before you make the request:
webClient.Encoding = Encoding.UTF8;
string previouslyWrongXml = webClient.DownloadString(url);

C# Get site source code with letters other than english

I'm trying to get a site's source in C# using
WebClient client = new WebClient();
string content = client.DownloadString(url);
And it gets it just fine.
However, the source code contains Hebrew characters which shows like Gibbrish in content variable.
What do I need to do for it to recognize it?

WebClient client = new WebClient();
client.Encoding = System.Text.UTF8Encoding.UTF8; // added
string content = client.DownloadString(url);
You have to specify the encoding, you are probably requesting ASCII by default and the content could be in UTF8. This is an example where the encoding is set to UTF8. If you are not sure what it is check the source manually first and then specify the encoding accordingly. For more info see Remarks in the documentation.

The problem is the Encoding of your WebClient. MSDN says:
... the method uses the encoding specified in the Encoding property to convert the resource to a String.
Solution: Set a specific Encoding like
client.Encoding = Encoding.UTF8;
and try it again
string content = client.DownloadString(url);
UTF8 should do the trick to encode also the hebrew characters.

How to read javascript file using HttpWebRequest in c#

I have a javascript file in a remote server, and when I use httpwebrequest it returns some weird characters.
Thr url is http://goo.gl/0Ug5QI
Is this kind of compressed contents?
static string GetScriptSource(string _url)
{
string _retValue = string.Empty;
HttpWebRequest hwr = (HttpWebRequest)WebRequest.Create(_url);
hwr.Method = "GET";
HttpWebResponse res = (HttpWebResponse)hwr.GetResponse();
StreamReader sr = new StreamReader(res.GetResponseStream());
return sr.ReadToEnd();
}
My code to read that script file's content is very simple.

Looking at the js source that you linked to, it could be that is has been gzipped. Try saving the source as a file and use 7zip or something to see if you can unzip it. There is a GZip library in C# so if it has been gzipped then you should be able to unzip it easily enough.
Although it's a Korean web site so maybe the encoding is not correct.
Either way it's not a problem with the code that you posted.

convert rtsp stream to http stream

In c# is there possibility that rtsp video stream is used "System.net.httpwebrequest" if not plz tell me another alternative .
// the URL to download the file from
string basepath = #"rtsp://ip.worldonetv.com:1935/live/ ";
// the path to write the file to
// string sFilePathToWriteFileTo = "d:\\Download";
// first, we need to get the exact size (in bytes) of the file we are downloading
Uri url = new Uri(basepath);
System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(url);
System.Net.HttpWebResponse response = (System.Net.HttpWebResponse)request.GetResponse();
response.Close();

You can formulate RtspRequests with my library.
You can then base64 encode the RtspRequest and put that as the body to the HttpRequest.
Add the content-length header which would be equal to the length of the base64 encoded rtsp request in the body.
Add the header rtsp/x-tunneled to HttpRequest and then sent it along.
You should get back a HttpResponse with the body containing a base64 encoded RtspResponse.
Base64 decode the Body of the HttpResponse and then use the RtspResponse class in my library to parse it.
The library is # http://net7mma.codeplex.com/
And there is a codeproject article # http://www.codeproject.com/Articles/507218/Managed-Media-Aggregation-using-Rtsp-and-Rtp
If you need anything else let me know!

There's no standard C# library to do this. You can't even do it with the various .NET DirectShow wrappers. I just had a coworker spend a month on this problem and he ended up writing his own C# wrapper on GStreamer. If you're planning to display the video, the easiest option is to embed the VLC ActiveX control.

HttpWebRequest an Unicode characters

I am using this code:
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
string result = null;
using (HttpWebResponse resp = (HttpWebResponse)req.GetResponse())
{
StreamReader reader = new StreamReader(resp.GetResponseStream());
result = reader.ReadToEnd();
reader.Close();
}
In result I get text like 003cbr /003e003cbr /003e (I think this should be 2 line breaks instead). I tried with the 2, 3 parameter versions of Streamreader but the string was the same. (the request returns a json string)
Why am I getting those characters, and how can I avoid them?

It's not really clear what that text is, but you're not specifying an encoding at the moment. What content encoding is the server using? StreamReader will default to UTF-8.
It sounds like actually you're getting some sort of oddly-encoded HTML, as U+003C is < and U+003E is >, giving <br /><br /> as the content. That's not JSON...
Two tests:
Use WebClient.DownloadString, which will detect the right encoding to use
See what gets shown using the same URL in a browser
EDIT: Okay, now that I've seen the text, it's actually got:
\u003cbr /\u003e
The \u part is important here - that's part of the JSON which states that the next four characters form ar the hex representation of a UTF-16 code unit.
Any JSON API used to parse that text should perform the unescaping for you.