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Why POST use Webrequest always fail but use html form is success?

I spent two days to debug but I can't find error's cause.
App client using WebRequest call servlet result is fail, WebException is "The operation has time out" but When I call servlet by POST method in html form is success. Here is code C#:
public string PostURLRequest(string URL, string postData)
{
try
{
System.Text.Encoding enc =
System.Text.Encoding.GetEncoding("shift_jis");
byte[] postDataBytes = System.Text.Encoding.ASCII.GetBytes(postData);
System.Net.HttpWebRequest req =
(System.Net.HttpWebRequest)System.Net.WebRequest.Create(URL);
req.ProtocolVersion = System.Net.HttpVersion.Version10;
req.Method = "POST";
req.ReadWriteTimeout = -1;
req.KeepAlive = false;
req.ContentType = "application/x-www-form-urlencoded";
req.ContentLength = postDataBytes.Length;
req.Timeout = 10*60*1000;
System.IO.Stream reqStream = req.GetRequestStream();
reqStream.Write(postDataBytes, 0, postDataBytes.Length);
reqStream.Close();
System.Net.WebResponse res = req.GetResponse();//----------> THROW EXCEPTION HERE
System.IO.Stream resStream = res.GetResponseStream();
System.IO.StreamReader sr = new System.IO.StreamReader(resStream, enc);
String text = sr.ReadToEnd();
sr.Close();
return text;
}
catch(System.Net.WebException ex)
{
if (ex.Status == System.Net.WebExceptionStatus.Timeout)
{
Console.WriteLine("Error: {0}", ex.Message);
}
return "NG";
}
}

I am trying to write a console app in c# that consume a web service running on tomcat, to perform a "PUT" method with an xml file

public static String TransferMessage(String uri, String resource,
String xml_data, Method httpmethod,
ReturnType returnType)
{
try
{
WebRequest request = WebRequest.Create(uri + resource);
request.Method = httpmethod.ToString();
request.ContentType = #"application/xml;";
//request.Headers.Add("Token", token);
request.Timeout = Convert.ToInt32((new TimeSpan(1, 0, 0)).TotalMilliseconds);
request.ContentLength = Encoding.UTF8.GetByteCount(xml_data);
if (httpmethod != Method.GET)
using (Stream stream = request.GetRequestStream())
{
stream.Write(Encoding.UTF8.GetBytes(xml_data), 0,
Encoding.UTF8.GetByteCount(xml_data));
stream.Flush();
stream.Close();
}
return getResponseContent(request.GetResponse());
}
catch(Exception e)
{
Console.WriteLine(e);
}
return null;
}
Main method:
var res_xml = MethodHelper.TransferMessage(endpoint, "/" + resource,xml,
MethodHelper.Method.PUT,
MethodHelper.ReturnType.XML);
I am getting this error
ERROR javax.xml.bind.UnmarshalException\n - with
linked exception:\n[org.xml.sax.SAXParseException; line Number: 1;
columnNumber: 1; Content is not allowed in prolog.]

try{
string contend = "";
using (var streamReader = new StreamReader(new FileInfo(#"C:\Users\absmbez\Desktop\temp\upload.xml").OpenRead()))
{
contend = streamReader.ReadToEnd();
}
HttpWebRequest webrequest = (HttpWebRequest)WebRequest.Create(url);
webrequest.Method = "PUT";
webrequest.ContentType = "application/xml";
Encoding enc = System.Text.Encoding.GetEncoding("utf-8");
byte[] requestData = enc.GetBytes(contend);
webrequest.ContentLength = requestData.Length;
using (var stream = webrequest.GetRequestStream())
{
stream.Write(requestData, 0, requestData.Length);
}
HttpWebResponse webresponse = (HttpWebResponse)webrequest.GetResponse();
StreamReader responseStream = new StreamReader(webresponse.GetResponseStream(), enc);
string result = string.Empty;
result = responseStream.ReadToEnd();
webresponse.Close();
return result;
}
catch (Exception e)
{
Console.WriteLine(e);
}

Login to instagram programmatically

I am trying to log in to instagram using web requests. I am having a bad time understanding what's going on. Getting this: The remote server returned an error: (403) Forbidden. What I have so far:
public static string csrf;
CookieContainer c1 = new CookieContainer();
private void button1_Click(object sender, EventArgs e)
{
string PostData = String.Format("csrfmiddlewaretoken={0}&username=ra123&password=ra12345678",getToken());
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("https://instagram.com/accounts/login/");
req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
req.KeepAlive = true;
req.AllowAutoRedirect = true;
req.CookieContainer = c1;
byte[] byteArray = Encoding.ASCII.GetBytes(PostData);
req.ContentLength = byteArray.Length;
Stream dataStream = req.GetRequestStream();
dataStream.Write(byteArray, 0, byteArray.Length);
dataStream.Flush();
dataStream.Close();
HttpWebResponse webResp = (HttpWebResponse)req.GetResponse();
Stream datastream = webResp.GetResponseStream();
StreamReader reader = new StreamReader(datastream);
string s = reader.ReadToEnd();
MessageBox.Show(s);
if (s.Contains("ra123"))
{
MessageBox.Show("Loggedin");
}
else
{
MessageBox.Show("Not");
}
}
string getToken()
{
string p = "<input type=\"hidden\" name=\"csrfmiddlewaretoken\" value=\"(.*)\"/>";
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("https://instagram.com/accounts/login/");
req.Method = "GET";
req.CookieContainer = c1;
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
Stream data = resp.GetResponseStream();
StreamReader sr = new StreamReader(data);
string src = sr.ReadToEnd();
Match m = Regex.Match(src, p);
if (m.Success)
{
return (m.Groups[1].Value.ToString());
}
return false.ToString();
}

The problem with the login is that the request needs to set the cookie at the header, and the container is not setting it since is changes at every login when you access from an unknown explorer. Here is what you can do:
WebResponse Response;
HttpWebRequest Request;
Uri url = new Uri("http://thewebpage.com:port/login/");
CookieContainer cookieContainer = new CookieContainer();
Request = (HttpWebRequest)WebRequest.Create(url);
Request.Method = "GET";
Request.CookieContainer = cookieContainer;
// Get the first response to obtain the cookie where you will find the "csrfmiddlewaretoken" value
Response = Request.GetResponse();
string Parametros = "csrfmiddlewaretoken=" + cookieContainer.GetCookies(url)["csrftoken"].Value + "&username=USER&password=PASSWORD&next="; // This whill set the correct url to access
Request = (HttpWebRequest)WebRequest.Create(url); // it is important to use the same url used for the first request
Request.Method = "POST";
Request.ContentType = "application/x-www-form-urlencoded";
Request.UserAgent = "Other";
// Place the cookie container to obtain the new cookies for further access
Request.CookieContainer = cookieContainer;
Request.Headers.Add("Cookie",Response.Headers.Get("Set-Cookie")); // This is the most important step, you have to place the cookies at the header (without this line you will get the 403 Forbidden exception
byte[] byteArray = Encoding.UTF8.GetBytes(Parametros);
Request.ContentLength = byteArray.Length;
Stream dataStream = Request.GetRequestStream();
dataStream.Responseite(byteArray, 0, byteArray.Length);
dataStream.Close();
Response = Request.GetResponse();

FYI, this won't solve your problem, but you need to learn to place your Stream and other objects that implement IDisposable into using blocks:
public static string csrf;
CookieContainer c1 = new CookieContainer();
private void button1_Click(object sender, EventArgs e)
{
string PostData = String.Format("csrfmiddlewaretoken={0}&username=ra123&password=ra12345678", getToken());
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("https://instagram.com/accounts/login/");
req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
req.KeepAlive = true;
req.AllowAutoRedirect = true;
req.CookieContainer = c1;
byte[] byteArray = Encoding.ASCII.GetBytes(PostData);
req.ContentLength = byteArray.Length;
using (Stream dataStream = req.GetRequestStream())
{
dataStream.Write(byteArray, 0, byteArray.Length);
dataStream.Flush();
dataStream.Close();
}
string s;
using (HttpWebResponse webResp = (HttpWebResponse)req.GetResponse())
{
using (Stream datastream = webResp.GetResponseStream())
{
using (StreamReader reader = new StreamReader(datastream))
{
s = reader.ReadToEnd();
}
}
}
MessageBox.Show(s);
if (s.Contains("ra123"))
{
MessageBox.Show("Loggedin");
}
else
{
MessageBox.Show("Not");
}
}
string getToken()
{
string p = "<input type=\"hidden\" name=\"csrfmiddlewaretoken\" value=\"(.*)\"/>";
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create("https://instagram.com/accounts/login/");
req.Method = "GET";
req.CookieContainer = c1;
string src;
using (HttpWebResponse resp = (HttpWebResponse)req.GetResponse())
{
using (Stream data = resp.GetResponseStream())
{
using (StreamReader sr = new StreamReader(data))
{
src = sr.ReadToEnd();
}
}
}
Match m = Regex.Match(src, p);
if (m.Success)
{
return (m.Groups[1].Value.ToString());
}
return false.ToString();
}

How to get value back from a web services in C#?

I am sending a URL and XML to a webservices, so that it will return me JSON about the result. I am here posting the request to the webservices how do I get the value from the webservices back. The value returned by the webservices is JSON. What should be the return type here and what should be returned to get the HTTP response status and body
public string HttpPostcredentials(string XML, string url)
{
try
{
HttpWebRequest req = WebRequest.Create(new Uri(url)) as HttpWebRequest;
req.Method = "POST";
byte[] buffer = Encoding.ASCII.GetBytes(XML);
req.ContentLength = buffer.Length;
req.ContentType = "application/xml";
Stream PostData = req.GetRequestStream();
PostData.Write(buffer, 0, buffer.Length);
PostData.Close();
}
catch (Exception e)
{
}
return null;
}

Is this what you are looking for:
var request = WebRequest.Create(string.Concat(serviceUrl, resourceUrl)) as HttpWebRequest;
if (request != null)
{
request.ContentType = "application/xml";
request.Method = "POST";
}
byte[] requestBodyBytes = Encoding.ASCII.GetBytes(XML);
request.ContentLength = requestBodyBytes.Length;
using (Stream postStream = request.GetRequestStream())
postStream.Write(requestBodyBytes, 0, requestBodyBytes.Length);
if (request != null)
{
var response = request.GetResponse() as HttpWebResponse;
if(response.StatusCode == HttpStatusCode.OK)
{
Stream responseStream = response.GetResponseStream();
if (responseStream != null)
{
var reader = new StreamReader(responseStream);
responseMessage = reader.ReadToEnd();
}
}
else
{
responseMessage = response.StatusDescription;
}
}

You need to get the Response from the HttpWebRequest
WebResponse result = req.GetResponse();

How to add parameters into a WebRequest?

I need to call a method from a webservice, so I've written this code:
private string urlPath = "http://xxx.xxx.xxx/manager/";
string request = urlPath + "index.php/org/get_org_form";
WebRequest webRequest = WebRequest.Create(request);
webRequest.Method = "POST";
webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.
webRequest.ContentLength = 0;
WebResponse webResponse = webRequest.GetResponse();
But this method requires some parameters, as following:
Post data:
_username:'API USER', // api authentication username
_password:'API PASSWORD', // api authentication password
How can I add these parameters into this Webrequest?

Use stream to write content to webrequest
string data = "username=<value>&password=<value>"; //replace <value>
byte[] dataStream = Encoding.UTF8.GetBytes(data);
private string urlPath = "http://xxx.xxx.xxx/manager/";
string request = urlPath + "index.php/org/get_org_form";
WebRequest webRequest = WebRequest.Create(request);
webRequest.Method = "POST";
webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.ContentLength = dataStream.Length;
Stream newStream=webRequest.GetRequestStream();
// Send the data.
newStream.Write(dataStream,0,dataStream.Length);
newStream.Close();
WebResponse webResponse = webRequest.GetResponse();

If these are the parameters of url-string then you need to add them through '?' and '&' chars, for example http://example.com/index.aspx?username=Api_user&password=Api_password.
If these are the parameters of POST request, then you need to create POST data and write it to request stream. Here is sample method:
private static string doRequestWithBytesPostData(string requestUri, string method, byte[] postData,
CookieContainer cookieContainer,
string userAgent, string acceptHeaderString,
string referer,
string contentType, out string responseUri)
{
var result = "";
if (!string.IsNullOrEmpty(requestUri))
{
var request = WebRequest.Create(requestUri) as HttpWebRequest;
if (request != null)
{
request.KeepAlive = true;
var cachePolicy = new RequestCachePolicy(RequestCacheLevel.BypassCache);
request.CachePolicy = cachePolicy;
request.Expect = null;
if (!string.IsNullOrEmpty(method))
request.Method = method;
if (!string.IsNullOrEmpty(acceptHeaderString))
request.Accept = acceptHeaderString;
if (!string.IsNullOrEmpty(referer))
request.Referer = referer;
if (!string.IsNullOrEmpty(contentType))
request.ContentType = contentType;
if (!string.IsNullOrEmpty(userAgent))
request.UserAgent = userAgent;
if (cookieContainer != null)
request.CookieContainer = cookieContainer;
request.Timeout = Constants.RequestTimeOut;
if (request.Method == "POST")
{
if (postData != null)
{
request.ContentLength = postData.Length;
using (var dataStream = request.GetRequestStream())
{
dataStream.Write(postData, 0, postData.Length);
}
}
}
using (var httpWebResponse = request.GetResponse() as HttpWebResponse)
{
if (httpWebResponse != null)
{
responseUri = httpWebResponse.ResponseUri.AbsoluteUri;
cookieContainer.Add(httpWebResponse.Cookies);
using (var streamReader = new StreamReader(httpWebResponse.GetResponseStream()))
{
result = streamReader.ReadToEnd();
}
return result;
}
}
}
}
responseUri = null;
return null;
}

For doing FORM posts, the best way is to use WebClient.UploadValues() with a POST method.

Hope this works
webRequest.Credentials= new NetworkCredential("API_User","API_Password");

I have a feeling that the username and password that you are sending should be part of the Authorization Header. So the code below shows you how to create the Base64 string of the username and password. I also included an example of sending the POST data. In my case it was a phone_number parameter.
string credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(_username + ":" + _password));
HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(Request);
webRequest.Headers.Add("Authorization", string.Format("Basic {0}", credentials));
webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.Method = WebRequestMethods.Http.Post;
webRequest.AllowAutoRedirect = true;
webRequest.Proxy = null;
string data = "phone_number=19735559042";
byte[] dataStream = Encoding.UTF8.GetBytes(data);
request.ContentLength = dataStream.Length;
Stream newStream = webRequest.GetRequestStream();
newStream.Write(dataStream, 0, dataStream.Length);
newStream.Close();
HttpWebResponse response = (HttpWebResponse)webRequest.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader streamreader = new StreamReader(stream);
string s = streamreader.ReadToEnd();

The code below differs from all other code because at the end it prints the response string in the console that the request returns. I learned in previous posts that the user doesn't get the response Stream and displays it.
//Visual Basic Implementation Request and Response String
Dim params = "key1=value1&key2=value2"
Dim byteArray = UTF8.GetBytes(params)
Dim url = "https://okay.com"
Dim client = WebRequest.Create(url)
client.Method = "POST"
client.ContentType = "application/x-www-form-urlencoded"
client.ContentLength = byteArray.Length
Dim stream = client.GetRequestStream()
//sending the data
stream.Write(byteArray, 0, byteArray.Length)
stream.Close()
//getting the full response in a stream
Dim response = client.GetResponse().GetResponseStream()
//reading the response
Dim result = New StreamReader(response)
//Writes response string to Console
Console.WriteLine(result.ReadToEnd())
Console.ReadKey()