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connect client to server and get a text file from it in C#

I would like to connect automatically from a client to a server with an IP address in C# and get a text file from the server.
What would be the best way to achieve this ?

WebClient
The simplest way to do so is using "WebClient". See https://msdn.microsoft.com/en-us/library/system.net.webclient(v=vs.110).aspx
This class has a function called
public string DownloadString(string address)
You can use this to download the text file to memory.
For more Methods (e.g. DownloadFile) visit the given link. Note: This Method might hang the window if executed in the UI-Thread while downloading the content. Either use a second Thread to do the stuff or use the asynchronous methods if possible.
In this case you would rather use this:
public Task<string> DownloadStringTaskAsync(string address)
More Information about Async: https://msdn.microsoft.com/en-us/library/dd537609(v=vs.110).aspx

It is easy to achieve using a WebRequest as follows.
// Create a request for the URL.
WebRequest request = WebRequest.Create("http://yourdomain.com/textfile");
// Get the response.
WebResponse response = request.GetResponse();
// Get the stream containing content returned by the server.
Stream dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();

HttpWebResponse text does not appear to be JSON

I am making a rest call in which I get a HttpWebResponse that contains data. It seems the data is serialized, and I am trying to get the plain text of the request. I have been using the chrome extension Advanced Rest client, which when calling the same request it is able to display the text version of the json response.
From what I have read on here, you are required to deserialize into the expected object. However, it is pretty clear that chrome plugin has no idea about the object type and can still print out plain text.
Is it possible to do the same in c#?
HttpWebRequest request = WebRequest.Create(address) as HttpWebRequest;
request.Method = "POST";
request.ContentType = "application/json";
// [code removed for setting json data via stream writer
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
// This is where I am trying to figure out how to get plain readable text out of response.GetResponseStream()
}
Edit: If I simply use a StreamReader to get the text from the response stream, I get a bunch of binary data and not the plain json text.
Edit: realized the problem had to do with compression. This can be closed.

I'm not sure if got it right, but you can get the response as a string doing this:
using (var sr = new StreamReader(response.GetResponseStream()))
{
text = sr.ReadToEnd();
}

Turned out my problem was due to compression. I realized the header contained "Content-Encoding: gzip" so I searched on how to unzip with gzip compression and then the text was proper json. Thanks all

Is it possible to access a webpage without a webbrowser?

I want to visit a web page (it has to be accessed, nothing needs to be read, modified, etc. Just accessed). I don't want to use webbrowser.

Just do a cURL GET request.
curl http://example.com/
And if you want to use C#, then
using System.Net;
string url = "https://www.example.com/";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream resStream = response.GetResponseStream();

Also, you can use Fiddler to send request to the remote server (it is very helpful for service debuging).

try to use WebClient class:
for example:
WebClient client = new WebClient ();
string reply = client.DownloadString (address);

How do I check for binary vs. text in an HttpWebRequest in c#?

Is there a way to determine if the response from an HttpWebRequest in C# contains binary data vs. text? Or is there another class or function I should be using to do this?
Here's some sample code. I'd like to know before reading the StreamReader if the content is not text.
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://www.someurl.com");
request.Method = WebRequestMethods.Http.Get;
using (WebResponse response = request.GetResponse())
{
// check somewhere in here if the response is binary data and ignore it
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
string responseDetails = reader.ReadToEnd().Trim();
}
}

In general, web sites will tell you in the Content-Type header what kind of data they're returning. You can determine that by getting the ContentType property from the response.
But sites have been known to lie. Or not say anything. I've seen both. If there is no Content-Type header or you don't want to trust it, then the only way you can tell what kind of data is there, is by reading it.
But then, if you don't trust the site, why are you reading data from it?

Communicating with an ASP website

I have a know a website that contains an open database of the result of an academic test.
http://nts.org.pk/NTSWeb/PPL_30Sep2012_Result/search.asp
I am expert with C# but newbie to web development.
Usually, using web browser, we can enter and roll number and server sends back the result. E.G. Use my Roll Num: 3912125
What I need to do is, use a C# application to communicate this roll null number and get anything, of my result. (any string is excepted, I will parse out my result from that string.)
How do I send query? when I don't know a list of possible query strings.
I tried this code:
string queryString = "RollNo=3912125";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(#"http://nts.org.pk/NTSWeb/PPL_30Sep2012_Result/search.asp");
request.UseDefaultCredentials = true;
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
byte[] requestBytes = Encoding.UTF8.GetBytes(queryString);
request.ContentLength = requestBytes.Length;
using (var requestStream = request.GetRequestStream())
{
requestStream.Write(requestBytes, 0, requestBytes.Length);
requestStream.Close();
}
WebResponse response = request.GetResponse();
textBox1.AppendText(((HttpWebResponse)response).StatusDescription);
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
string responseFromServer = reader.ReadToEnd();
textBox1.AppendText(responseFromServer);
reader.Close();
dataStream.Close();
response.Close();

You have to append the querystring to the url like this:
string queryString = "RollNo=3912125";
string url = String.Format(#"http://foo/search.asp?{0}", queryString);
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);

You should take a look at the code in my answer to C# https login and download file. It gives a good demonstration of how to perform a POST request. As far as knowing what's valid to use for the query-formatted string in your POST, it's simply a matter of looking for appropriate input elements in the page content. It looks like what you have (RollNo) is correct. You may, however, need to also add the submit button value to your request as well depending on how the server behaves, giving you something like. RollNo=3912125&submit=submit.

You're most of the way there. Your queryString should look like RollNo=3912125&Submit=+Search+. When you are calling WebRequest.Create, the Url should in fact be http://nts.org.pk/NTSWeb/PPL_30Sep2012_Result/result.asp.
The rest of your code should work, though the answer #JamieSee recommended to you has some very good advice about wrapping things in using blocks correctly