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HttpWebRequest.getResponse() returning NULL

I am attempting to create a console app that sends a WebRequest to a website so that I can get some information back from it in JSON format. Once I build up the request and try to get response I just want to simply print out the data, but when I call httpWebRequest.getResponse() it returns NULL.
I have tried multiple other methods of sending the data to the the url but those are all giving me like 404, or 400 errors, etc. This method at least isn't giving me any error, just a NULL.
Here is a snapshot of the documentation I am using for the API (albeit the docs aren't complete yet):
Here is the console app code that I have right now:
try
{
var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://api.remot3.it/apv/v27/user/login");
httpWebRequest.ContentType = "application/json";
httpWebRequest.Method = "POST";
httpWebRequest.Headers.Add("developerkey", "***KEY***");
using (var streamWriter = new
StreamWriter(httpWebRequest.GetRequestStream()))
{
string json = new JavaScriptSerializer().Serialize(new
{
email = "***EMAIL***",
password = "***PASSWORD***"
});
Console.WriteLine(json);
streamWriter.Write(json);
}
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
var result = streamReader.ReadToEnd();
Console.WriteLine(result);
Console.ReadLine();
}
}catch(Exception e)
{
Console.WriteLine(e.Message);
Console.WriteLine(e.StackTrace);
Console.ReadLine();
}
Expected output is some JSON data, but I am getting a NULL back from getResponse().

Try to serialize the credential in your form and for header send as parameter for this class.
Check below for my code. It is not 100 % fit to your requirement, but atleast it will help to get through your logic.
Here is what I get Json Response from this code. Its work Perfect. Please remember to add timeout option on your webrequest and at the end close the streamreader and stream after completing your task. please check this code.
public static string httpPost(string url, string json)
{
string content = "";
byte[] bs;
if (json != null && json != string.Empty)
{
bs = Encoding.UTF8.GetBytes(json);
}
else
{
bs = Encoding.UTF8.GetBytes(url);
}
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url);
req.Method = "POST";
if (json != string.Empty)
req.ContentType = "application/json";
else
req.ContentType = "application/x-www-form-urlencoded";
req.KeepAlive = false;
req.Timeout = 30000;
req.ReadWriteTimeout = 30000;
//req.UserAgent = "test.net";
req.Accept = "application/json";
req.ContentLength = bs.Length;
using (Stream reqStream = req.GetRequestStream())
{
reqStream.Write(bs, 0, bs.Length);
reqStream.Flush();
reqStream.Close();
}
using (WebResponse wr = req.GetResponse())
{
Stream s = wr.GetResponseStream();
StreamReader reader = new StreamReader(s, Encoding.UTF8);
content = reader.ReadToEnd();
wr.Close();
s.Close();
reader.Close();
}
return content;
}

How to set TimeOut For StreamWriter?

I am using this code to receive data from Server. But I don't know how to set timeout for it. I receive a string from PostInput Model: ContentType, Json, WebRequest.
And this is my code:
public string PostMethod(PostInput Input)
{
try
{
var httpWebRequest = (HttpWebRequest)WebRequest.Create(Input.WebRequest);
httpWebRequest.ContentType = Input.ContentType;
httpWebRequest.Method = "POST";
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
{
streamWriter.Write(Input.Json);
streamWriter.Flush();
streamWriter.Close();
}
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
string result;
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
result = streamReader.ReadToEnd();
}
return result;
}
catch (Exception ex)
{
return string.Empty;
}
}

you can try an consider using WebClinet like so
using (WebClient client = new WebClient())
{
using (Stream stream = client.OpenWrite(Input.WebRequest.RequestUri))
using (StreamWriter reader = new StreamWriter(stream))
{
stream.WriteTimeout = 200;
}
}

You might use HttpWebRequest class's Timeout property.
Simple code like:
httpWebRequest.ContentType = Input.ContentType;
httpWebRequest.Method = "POST";
httpWebRequest.Timeout= 10000; // 10 seconds
HttpWebRequest.Timeout

tnks friends
i found new way,
i ping the ip and if it available Then calling StreamWriter
this Is my Reaserch Result:
public string PostMethod(PostInput Input)
{
try
{
var httpWebRequest = (HttpWebRequest)WebRequest.Create(Input.WebRequest);
httpWebRequest.ContentType = Input.ContentType;
httpWebRequest.Method = "POST";
PingReply Objping = new Ping().Send(IPAddress.Parse(Input.Address), 1000);
string result;
if (Objping.Status == IPStatus.Success)
{
using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
{
streamWriter.Write(Input.Json);
streamWriter.Flush();
streamWriter.Close();
}
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
{
result = streamReader.ReadToEnd();
}
return result;
}
return null;
}

HttpWebResponse hangs/freezes when running in a WebAPI

I am using a C# WebAPI project which would call an external API based on its URL. However, when I am trying to retrieve the data back, it hangs/freezes.
The code where it stops is:
var response = (HttpWebResponse)await Task.Factory.FromAsync<WebResponse>(request.BeginGetResponse, request.EndGetResponse, null);
I don't understand why it is stopping though. Could it be interfering with the API request I am also making? When I run this code as part of a unit test, I would get a response back within seconds. I don't think it is the API service itself, I think it is my code. I have already tried various API URLS. None of them work.
My full code is:
public static async Task<string> CallWebAPi<T>(string url)
{
string returnValue;
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
request.ContentType = "application/json";
request.Method = "GET";
var response = (HttpWebResponse)await Task.Factory.FromAsync<WebResponse>(request.BeginGetResponse, request.EndGetResponse, null);
Stream stream = response.GetResponseStream();
StreamReader strReader = new StreamReader(stream);
returnValue = await strReader.ReadToEndAsync();
return returnValue;
}
Any help would be appreciated.

Possible deadlock ConfigureAwait(false), here are a good explanation from Stephen on what cause deadlocks.
var response = (HttpWebResponse)await Task.Factory.FromAsync<WebResponse>(request.BeginGetResponse, request.EndGetResponse, null).ConfigureAwait(false);

As a workaround you can use the synchronous functions, create a Task and await this task:
var response = await Task.Run(() =>
{
return (HttpWebResponse)request.GetResponse();
});

This is how i do my Request. Each Part is in an own Function. Its create the Request and you can get the Response synchronous.
public HttpWebRequest CreateRequest(string Url, string Method, string ContentType, object Content, List<RequestHeader> headers)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
request.Method = Method;
if (!string.IsNullOrWhiteSpace(ContentType)) request.ContentType = ContentType;
else if(Content != null) request.ContentType = "application/json";
if (Content != null)
{
var postData = Newtonsoft.Json.JsonConvert.SerializeObject(Content);
var data = Encoding.ASCII.GetBytes(postData);
request.ContentLength = data.Length;
using (var stream = request.GetRequestStream())
{
stream.Write(data, 0, data.Length);
}
}
foreach(RequestHeader header in Headers)
{
request.Headers.Add(header.Type, header.Value);
} //class at the end.
return request;
}
public string GetResponse(HttpWebRequest request)
{
var retval = "";
try
{
var response = (HttpWebResponse)request.GetResponse();
retval = ReadResponse(response);
response.Close();
}
catch (Exception ex)
{
resolveException(ex.Message);
}
return retval;
}
public string ReadResponse(HttpWebResponse response)
{
var retval = "";
try
{
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
var responseText = reader.ReadToEnd();
retval = responseText;
}
}
catch (Exception ex)
{
resolveException(ex.Message);
}
return retval;
}
public class RequestHeader
{
public HttpRequestHeader Type { get; set; }
public string Value { get; set; }
}

you dont need Task.Factory.FromAsync. HttpWebRequest already supports asynchronous operations.
You have defined a generic method CalWebApi<T> but have never used a generic type
if your operation is async, use this.
public async Task<T> CalWebApiAsync<T>(string url)
{
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
request.ContentType = "application/json";
request.Method = "GET";
using (var response = await request.GetResponseAsync())
{
using (var responseStream = response.GetResponseStream())
{
using (var streamReader = new StreamReader(responseStream))
{
var stringResult = await streamReader.ReadToEndAsync();
T objectResult = Newtonsoft.Json.JsonConvert.DeserializeObject<T>(stringResult);
return objectResult;
}
}
}
}
var result = await CallWebApiAsync<YourType>("exteranlapiurl");
if your operation is not async, use this..
public T CalWebApi<T>(string url)
{
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
request.ContentType = "application/json";
request.Method = "GET";
using (var response = request.GetResponse())
{
using (var responseStream = response.GetResponseStream())
{
using (var streamReader = new StreamReader(responseStream))
{
var stringResult = streamReader.ReadToEnd();
T objectResult = Newtonsoft.Json.JsonConvert.DeserializeObject<T>(stringResult);
return objectResult;
}
}
}
}
var result = CallWebApi<YourType>("exteranlapiurl");

Below c# code is not reading websites or webpage from given urls

WebRequest request = WebRequest.Create(url);
WebRequest.DefaultWebProxy = null;
request.Proxy = null;
WebResponse response = request.GetResponse();
Stream data = response.GetResponseStream();
using (StreamReader sr = new StreamReader(data))
{
html = sr.ReadToEnd();
}
The above code not able to read/download the following webpages:
1) https://en.wikipedia.org/wiki/Unified_Payments_Interface
2) http://www.npci.org.in/UPI_Background.aspx

This may help you below code contains for both to get and post data:
public static string PostContent(this Uri url, string body, string contentType = null)
{
var request = WebRequest.Create(url);
request.Method = "POST";
if (!string.IsNullOrEmpty(contentType)) request.ContentType = contentType;
using (var requestStream = request.GetRequestStream())
{
if (!string.IsNullOrEmpty(body)) using (var writer = new StreamWriter(requestStream)) { writer.Write(body); }
using (var response = request.GetResponse() as HttpWebResponse)
{
using (var stream = response.GetResponseStream())
using (var reader = new StreamReader(stream))
{
return reader.ReadToEnd();
}
}
}
}
public static string GetContent(this Uri url)
{
WebClient client = new WebClient();
try
{
using (client)
{
client.Encoding = Encoding.UTF8;
return client.DownloadString(url);
}
}
catch (WebException)
{
return "";
}
finally
{
client.Dispose();
client = null;
}
}

please note that .aspx file extension design the server-side page and in consequence you will be able to download only the html page that display when you navigate on these sites (this is the same for .php files).
but if you want to download the frontend view this should work :
using System.Net;
...
WebClient client = new WebClient();
client.DownloadFile("Your url","download location");

Get real-time data from a http long lived web service

I have a http long lived web service. If it has new data it will push to client using http GET. How can I receive real-time data from http long lived web service with HttpWebRequest c#?

If you wanted to get data using Get, you can use this (the response is synchronous when you use GetResponse):
public string GetMessageViaGet(string endPoint)
{
HttpWebRequest request = CreateWebRequest(endPoint);
using (var response = (HttpWebResponse)request.GetResponse())
{
var responseValue = string.Empty;
if (response.StatusCode != HttpStatusCode.OK)
{
string message = String.Format("Request failed. Received HTTP {0}", response.StatusCode);
throw new ApplicationException(message);
}
// grab the response
using (var responseStream = response.GetResponseStream())
{
using (var reader = new StreamReader(responseStream))
{
responseValue = reader.ReadToEnd();
}
}
return responseValue;
}
}
private HttpWebRequest CreateWebRequest(string endPoint)
{
var request = (HttpWebRequest)WebRequest.Create(endPoint);
request.Method = "GET";
request.ContentLength = 0;
request.ContentType = "text/xml";
return request;
}

If you want to get data via post, do this
public string GetMessageViaPost(string endPoint, string paramtersJson)
{
string responseValue;
byte[] bytes = Encoding.UTF8.GetBytes(paramtersJson);
HttpWebRequest request = CreateWebRequest(endPoint, bytes.Length);
using (var requestStream = request.GetRequestStream())
{
requestStream.Write(bytes, 0, bytes.Length);
}
using (var response = (HttpWebResponse)request.GetResponse())
{
if (response.StatusCode != HttpStatusCode.OK)
{
string message = String.Format("POST failed. Received HTTP {0}", response.StatusCode);
throw new ApplicationException(message);
}
// grab the response
using (var responseStream = response.GetResponseStream())
{
using (var reader = new StreamReader(responseStream))
{
responseValue = reader.ReadToEnd();
}
}
}
return responseValue;
}
private HttpWebRequest CreateWebRequest(string endPoint, Int32 contentLength)
{
var request = (HttpWebRequest)WebRequest.Create(endPoint);
request.Method = "POST";
request.ContentLength = contentLength;
request.ContentType = "application/json";// "application/x-www-form-urlencoded";
return request;
}