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Post data to a open URL without landing on the page c# asp.net

I am working on a site that sends data to another website and it has a landing page with a URL by using. The issue is I do not want to do the REdirect I just want it to send data to that page and continue with the code under it.
The other Site doesn't have API's how can I do this?
I have been looking at examples all of them are referring to API url's with log-in authentication but this URL does not require a log in just send in the data with the URL(www.example.come/submit?Firstname=Firstname;LastName=LastName;)
Something like that without actually redirecting the page to that site.

You can use the WebRequest
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create ("http://www.contoso.com/PostAccepter.aspx ");
// Set the Method property of the request to POST.
request.Method = "POST";
// Create POST data and convert it to a byte array.
string postData = "This is a test that posts this string to a Web server.";
byte[] byteArray = Encoding.UTF8.GetBytes (postData);
// Set the ContentType property of the WebRequest.
request.ContentType = "application/x-www-form-urlencoded";
// Set the ContentLength property of the WebRequest.
request.ContentLength = byteArray.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream ();
// Write the data to the request stream.
dataStream.Write (byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close ();
// Get the response.
WebResponse response = request.GetResponse ();
// Display the status.
Console.WriteLine (((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream ();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader (dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd ();
// Display the content.
Console.WriteLine (responseFromServer);
// Clean up the streams.
reader.Close ();
dataStream.Close ();
response.Close ();
You can read more about this Here

Proper Way to open this URL in a C# app

I have a URL that I want to open in my C# app. This URL is used to talk to a communications device, not an internet web site. I have gotten by (I think) all the cert stuff. But the text I get back in the program IS NOT the same thing that CORRECTLY displays when I use a web browser.
Here's the code.
using System;
using System.IO;
using System.Net;
using System.Text;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
using System.Web;
namespace VMLConnStatus
{
class Program
{
static void Main(string[] args)
{
System.Net.ServicePointManager.CertificatePolicy = new MyPolicy();
// Create a request for the URL: https://192.168.30.15/cgi-bin/connstatus?202
String url = "https://192.168.30.15/cgi-bin/";
String data = "connstatus?202";
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create(url);
// Set the Method property of the request to POST.
request.Method = "POST";
// Create POST data and convert it to a byte array.
string postData = data;
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Set the ContentType property of the WebRequest.
request.ContentType = "application/x-www-form-urlencoded";
// Set the ContentLength property of the WebRequest.
request.ContentLength = byteArray.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream();
// Write the data to the request stream.
dataStream.Write(byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close();
// Get the response.
WebResponse response = request.GetResponse();
// Display the status.
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseFromServer);
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();
Console.ReadLine();
}
}
public class MyPolicy : ICertificatePolicy
{
public bool CheckValidationResult(ServicePoint srvPoint,
X509Certificate certificate, WebRequest request,
int certificateProblem)
{
//Return True to force the certificate to be accepted.
return true;
}
}
}
The result, though not perfectly displayed in Chrome, should be:
NA NA NA NA 4c:cc:34:02:6d:26 00:23:A7:24:A3:B6
But the text I get in the console window is:
Ok
<HTML>
<HEAD><TITLE>Index of cgi-bin/</TITLE></HEAD>
<BODY BGCOLOR="#99cc99" TEXT="#000000" LINK="#2020ff" VLINK="#4040cc">
<H4>Index of cgi-bin/</H4>
<PRE>
. 15Jun2014 09:48
0
.. 15Jun2014 09:48
0
connstatus 15Jun2014 09:48
19580
firmwarecfg 15Jun2014 09:48
45736
webcm 15Jun2014 09:48
23836
</PRE>
<HR>
<ADDRESS><A HREF="http://www.acme.com/software/mini_httpd/">mini_httpd/1.19 19de
c2003</A></ADDRESS>
</BODY>
</HTML>
Not EVEN close to the same thing.
What am I doing wrong?
Chuck
UPDATE: Code changed. URL, GET, and request writing (presuming I understood the directions). New code is:
static void Main(string[] args)
{
System.Net.ServicePointManager.CertificatePolicy = new MyPolicy();
// Create a request for the URL: https://192.168.30.15/cgi-bin/connstatus?202
String url = "https://192.168.30.15/cgi-bin/connstatus?202";
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create(url);
// Set the Method property of the request to POST.
request.Method = "GET";
// Set the ContentType property of the WebRequest.
request.ContentType = "application/x-www-form-urlencoded";
// Get the request stream.
//Now it throws an exception here--------------------------------
//"Cannot send a content-body with this verb-type."
Stream dataStream = request.GetRequestStream();
// Close the Stream object.
dataStream.Close();
// Get the response.
WebResponse response = request.GetResponse();
// Display the status.
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseFromServer);
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();
Console.ReadLine();
}

You are using http method POST but the url you have in the comment looks more like GET so then you probably need WebRequest.Create(url + data).
The incorrect response is the index page for https://192.168.30.15/cgi-bin/ which if you put into Chrome will give you the same "wrong" response.
You might not need to write any data to the request stream and can change the Method and ContentType for the request.

The solution required two parts.
First, doing the proper things, thus a total code rework.
I had the dreaded "The server committed a protocol violation. Section=ResponseHeader Detail=Header name is invalid". I tried to make the programatic solution for this work, but it is a .NET 2.0 solution and I was not able to figure it out in .NET4+. So, I edited the .config file and went on.
Here's the final code:
//Initialization
HttpWebRequest WebReq = (HttpWebRequest)WebRequest.Create(#"https://192.168.30.15/cgi-bin/connstatus?202");
//method is GET.
WebReq.Method = "GET";
//Get the response handle
HttpWebResponse WebResp = (HttpWebResponse)WebReq.GetResponse();
//read the response
Stream Answer = WebResp.GetResponseStream();
StreamReader _Answer = new StreamReader(Answer);
//display it
Console.WriteLine(_Answer.ReadToEnd());
//pause for the ENTER key
Console.ReadLine();
This was added to the .config file in the debug folder (and would be added in the Release folder also..... using VS2013)
<system.net>
<settings>
<httpWebRequest useUnsafeHeaderParsing = "true"/>
</settings>
</system.net>
Thank-you to everyone that replied. The inspiration helped me get to the solution.

HttpWebRequest needs to wait 5 seconds to work properly in PUT method

I am trying to use an API and I don't have any problems with GET and POST but PUT isn't working. I tried with a lot of different examples and finally by chance I discovered that waiting more that 5 seconds (with 5000ms it is not working and with 5100ms it does) it starts working properly. But why is that happening? And how can I avoid this? 5 seconds for each registry update is to much waiting and I really don't understand why POST works well without waiting and PUT needs 5 seconds to work.
Here I put the method that I am using with the Thread.Sleep(5100). As I said without this line when I make WebResponse response = request.GetResponse(); gives me an error.
public void call(string url, object jsonObj)
{
try
{
// Create a request using a URL that can receive a post.
HttpWebRequest request = (HttpWebRequest) HttpWebRequest.Create(urlSplio);
// Create POST data and convert it to a byte array.
request.Method = "PUT";
// Set the ContentType property of the WebRequest.
request.ContentType = "application/json";
request.Credentials = new NetworkCredential(WebConfigurationManager.AppSettings["User"], "WebConfigurationManager.AppSettings["Key"]");
string json = JsonConvert.SerializeObject(jsonObj);
byte[] byteArray = Encoding.UTF8.GetBytes(json);
// Set the ContentLength property of the WebRequest.
request.ContentLength = byteArray.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream();
// Write the data to the request stream.
dataStream.Write(byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close();
Thread.Sleep(5100);
// Get the response.
WebResponse response = request.GetResponse();
// Display the status.
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseFromServer);
// Clean up the streams.
dataStream.Close();
response.Close();
}
catch (Exception ex)
{
}
}

I think you might want to rewrite the response stream code
Take a look at this walkthrough on MS MS walkthrough
private byte[] GetURLContents(string url)
{
// The downloaded resource ends up in the variable named content.
var content = new MemoryStream();
// Initialize an HttpWebRequest for the current URL.
var webReq = (HttpWebRequest)WebRequest.Create(url);
// Send the request to the Internet resource and wait for
// the response.
// Note: you can't use HttpWebRequest.GetResponse in a Windows Store app.
using (WebResponse response = webReq.GetResponse())
{
// Get the data stream that is associated with the specified URL.
using (Stream responseStream = response.GetResponseStream())
{
// Read the bytes in responseStream and copy them to content.
responseStream.CopyTo(content);
}
}
// Return the result as a byte array.
return content.ToArray();
}

Parse JSON to Object fails

I am trying to parse JSON into an object, yet it keeps failing.
I keep on getting the error:
The type or namespace name 'DataContractJsonSerializer' does not exist in the namespace 'System.Runtime.Serialization.Json' (are you missing an assembly reference?)
But so far all the references have been added, but somehow it is still not functioning.
Am I doing the right thing here?
The code I have so far is as follows:
public Json_Connection ()
{
// Create a request for the URL.
WebRequest request = WebRequest.Create (
"http://10.190.80.248/WebService/webservice.asmx/getStudentID?id=1");
// If required by the server, set the credentials.
request.ContentType = "application/json";
request.Credentials = CredentialCache.DefaultCredentials;
// Get the response.
WebResponse response = request.GetResponse ();
// Display the status.
Console.WriteLine (((HttpWebResponse)response).StatusDescription);
// 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 ();
// Display the content.
Console.WriteLine (responseFromServer);
// Clean up the streams and the response.
XmlSerializer serializer = new DataContractJsonSerializer (Json.GetType(), new Type[] { typeof(Json) });
Json flippo = (Json)serializer.Deserialize (reader);
}
I use a MAC,so no windows folders or .net on this mac

You need to add a reference to System.Runtime.Serialization to your project. This dll should be included as part of the standard Xamarin distribution.
Alternatively, you may want to try using Newtonsoft.Json, which is a great Json package available for Xamarin.

Get the source of some website from asp.net code

Is there any way that I could get the source of a website (as a string preferably), let's say www.google.com, from some c# code inside code behind of asp.net website?
edit: of course i mean html code - in every browser you can view it using "view source" in context menu.

Assuming you want to retrieve the html:
class Program
{
static void Main(string[] args)
{
using (WebClient client = new WebClient())
using (Stream stream = client.OpenRead("http://www.google.com"))
using (StreamReader reader = new StreamReader(stream))
{
Console.WriteLine(reader.ReadToEnd());
}
}
}

For C#, I prefer to use HttpWebRequest over WebClient because you can have more option in the future like having GET/POST parameter, using Cookies, etc.
You can have a shortest explication at MSDN.
Here is the example from MSDN:
// Create a new HttpWebRequest object.
HttpWebRequest request=(HttpWebRequest) WebRequest.Create("http://www.contoso.com/example.aspx");
// Set the ContentType property.
request.ContentType="application/x-www-form-urlencoded";
// Set the Method property to 'POST' to post data to the URI.
request.Method = "POST";
// Start the asynchronous operation.
request.BeginGetRequestStream(new AsyncCallback(ReadCallback), request);
// Keep the main thread from continuing while the asynchronous
// operation completes. A real world application
// could do something useful such as updating its user interface.
allDone.WaitOne();
// Get the response.
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream streamResponse = response.GetResponseStream();
StreamReader streamRead = new StreamReader(streamResponse);
string responseString = streamRead.ReadToEnd();
Console.WriteLine(responseString);
// Close the stream object.
streamResponse.Close();
streamRead.Close();
// Release the HttpWebResponse.
response.Close();

it's not the most obvious (and the best) way but i found out that in windows forms you can use WebBrowser control (if you actually need it), fill it's Url property with the url you need and when it's loaded, read the DocumentText property - it contains the html code of the viewed site.