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How to read http response of multi-part stream in c#

I need to receive response from a http server using c#.The response is a multi-part stream; the header would contain
Content-Type: multipart/x-mixed-replace; boundary=userdata
The body of response would be similar to below:
--userdata
Content-type: text/plain
Content-length: <length-of-content>
UserId: <user-Id>
ParentId: <parent-Id>
ParentName: <parent-name>
Time: <time>
--userdata
Content-type: text/plain
Content-length: <length-of-content>
UserId: <user-Id>
ParentId: <parent-Id>
ParentName: <parent-name>
Time: <time>
I need to recieve the response and save these information continuously in
List<UserData>
which contains the list of UserData class having information of user.
Http response url is like
http://username:password#userIp:port-number/transactionStream
I have written following code but no result, Please help:
NetworkCredential networkCredential = new NetworkCredential(this.UserName, this.Password);
string requestingURL = "http://" + this.UserName + ":" + this.Password + "#" +this.UserIp+ ":" + this.PortNo + "/transactionDataStream";
Uri uri = new Uri(requestingURL);
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.Credentials = networkCredential;
HttpWebResponse Answer = (HttpWebResponse)request.GetResponse();
Stream aStream = Answer.GetResponseStream();
StreamReader aStreamReader = new StreamReader(aStream);
string response = aStreamReader.ReadToEnd();

I've used this before and it works well. StreamingMultipartFormDataParser
The Http Multipart Parser does it exactly what it claims on the tin: parses multipart/form-data. This particular parser is well suited to parsing large data from streams as it doesn't attempt to read the entire stream at once and produces a set of streams for file data.

HTTP request with post 404 not found

I used the top answer from HTTP request with post
however an error pops up in visual studio saying 404 remote server not found.
The website exists, it is a rails app bounded to the ip address of my router.
Using the following url in the browser updates the attribute of the applicant entity in the rails app. However using the c# app to do this is not working.
http://<ADDRESS HERE>:3000/api/v1/applicants/update?id=2&door=true
I have the ff:
using System.IO;
using System.Net;
using System.Text;
I used the following code inside a btn click
private void button1_Click (object sender, EventArgs e){
var request = (HttpWebRequest)WebRequest.Create("http://<ADDRESS HERE>:3000/api/v1/applicants/update");
var postData = "id=2";
postData += "&door=true";
var data = Encoding.ASCII.GetBytes(postData);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = data.Length;
using (var stream = request.GetRequestStream())
{
stream.Write(data, 0, data.Length);
}
var response = (HttpWebResponse)request.GetResponse();
var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
}

Are you sure you need to perform a POST request and not a GET request? I'm asking, because there seems to be inconsistency in your question. First you say you want to get to the url
http://<ADDRESS HERE>:3000/api/v1/applicants/update?id=2&door=true
which is a url with querystring params, but in the code you separate the querystring and send the params as POST data.
The GET request would look something like this
GET http://<ADDRESS HERE>:3000/api/v1/applicants/update?id=2&door=true HTTP/1.1
Host: <ADDRESS HERE>
... (more headers)
And the POST request:
POST http://<ADDRESS HERE>:3000/api/v1/applicants/update HTTP/1.1
Host: <ADDRESS HERE>
Content-type: application/x-www-form-urlencoded
... (more headers)
id=2&door=true

REST API PATCH request

I'm trying to send requests and get responses from MailChimp API . . so far, GET, POST and DELETE are working good however, PATCH always results to Bad Request can you identify the error in this code?
string data = "{\"name\": \"TestListTWOTWOTWO\"}";
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(uri);
request.Headers[HttpRequestHeader.Authorization] = accessToken;
request.Method = "PATCH";
request.ContentType = "text/plain;charset=utf-8";
System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
byte[] bytes = encoding.GetBytes(data);
request.ContentLength = bytes.Length;
using (Stream requestStream = request.GetRequestStream())
{
// Send the data.
requestStream.Write(bytes, 0, bytes.Length);
}
var response = (HttpWebResponse)request.GetResponse();
var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
the error occus on the line with request.GetResponse();
it is an unhandled WebException saying The remote server returned an error: (400) Bad Request
after checking the error response, here's the what it says
"Your request doesn't appear to be valid JSON:
\nParse error on line 1:\nPATCH /3.0/lists/9bb\n^\n
Expected one of: 'STRING', 'NUMBER', 'NULL', 'TRUE', 'FALSE', '{', '['"

Many C# libraries seem to try to use the Expect: 100-Continue header, which MailChimp/Akamai has a problem with when combined with PATCH. You have two options.
Turn off Expect: 100-Continue in your HTTP library. In one C# library, you do that with a line of code like Client.DefaultRequestHeaders.ExpectContinue = False
Tunnel the PATCH request through HTTP POST using the X-Http-Method-Override header. Here's more details on that header.

Cause PATCH is a quite new RFC, so you would not expect that more then a few services support it at all. You'd better check that if the service supports it.
You send request using json format, but set content type to "text/plain" is that OK?

.NET C# using HTTPrequest similar to Curl script

I´m using .NET C# and want to use HTTPrequest to make a POST in the same way as it is written in Curl:
curl
--header ’Accept: text/html’
--user ’test1:password’
--Form ’wait=0’
--Form ’data=#data.csv;type=text/csv’
some URL address here
I´m getting Error 500 Internal error from the Internet server.
The data to be send is a CSV file.
My source code in C#:
string data = "Time, A, B\n20120101, 100, 24\n20120102\n, 101, 27";
// Create a request using a URL that can receive a post.
request = WebRequest.Create(url);
//Set authorization
request.Credentials = new NetworkCredential(username, password);
// Set the Method property of the request to POST.
request.Method = "POST";
// Create POST data and convert it to a byte array.
byte[] byteArray = Encoding.UTF8.GetBytes(data);
// 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.
dataStream = request.GetRequestStream();
// Write the data to the request stream.
dataStream.Write(byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close();
// Get the original response.
WebResponse response = request.GetResponse();
this.Status = ((HttpWebResponse)response).StatusDescription;
// Get the stream containing all content returned by the requested server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content fully up to the end.
string responseFromServer = reader.ReadToEnd();
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();
What am I doing wrong?

cURL uses the multipart/form-data content type to create its requests. I think this is required in your case as you are passing both a text parameter and a file. Sadly the .Net framework does not appear to have built in support for creating this content type.
There is a question on SO that gives example code for how to do it yourself here: Multipart forms from C# client
For reference the HTTP request generated by that cURL command looks something like this:
POST http://www.example.com/example HTTP/1.1
Authorization: Basic J3Rlc3Q6cGFzc3dvcmQn
User-Agent: curl/7.33.0
Host: www.example.com
Accept: text/html
Connection: Keep-Alive
Content-Length: 335
Expect: 100-continue
Content-Type: multipart/form-data; boundary=------------------------99aa46d554951aa6
--------------------------99aa46d554951aa6
Content-Disposition: form-data; name="'wait"
0'
--------------------------99aa46d554951aa6
Content-Disposition: form-data; name="'data"; filename="data.csv"
Content-Type: text/csv'
Time, A, B\n20120101, 100, 24\n20120102\n, 101, 27
--------------------------99aa46d554951aa6--

Doesn't data need to be URL encoded for a form post? http://en.wikipedia.org/wiki/POST_%28HTTP%29#Use_for_submitting_web_forms

Send http request to server without expecting a response

I have a need to send a POST http request to a server ,but it should not expect a response. What method should i use for it ?
I have been using
WebRequest request2 = WebRequest.Create("http://local.ape-project.org:6969");
request2.Method = "POST";
String sendcmd = "[{\"cmd\":\"SEND\",\"chl\":3,\"params\":{\"msg\":\"Helloworld!\",\"pipe\":\"" + sub1 + "\"},\"sessid\":\"" + sub + "\"}]";
byte[] byteArray2 = Encoding.UTF8.GetBytes(sendcmd);
Stream dataStream2 = request2.GetRequestStream();
dataStream2.Write(byteArray2, 0, byteArray2.Length);
dataStream2.Close();
WebResponse response2 = request2.GetResponse();
to send a request and get back a response. This works fine if the request will get a response back from the server. But, for my need, i just need to send a POST request. And there will be no response associated with the request i am sending. How do i do it ?
If i use the request2.GetRespnse() command , i get an error that "The connection was closed unexpectedly"
Any help will be appreciated. thanks

If you're using the HTTP protocol, there has to be a response.
However, it doesn't need to be a very big response:
HTTP/1.1 200 OK
Date: insert date here
Content-Length: 0
\r\n

refer to this answer.
What you are looking for, I think, is the Fire and Forget pattern.

HTTP requires response as already mentioned by Mike Caron. But as a quick (dirty) fix you could catch the "connnection closed unexpectedly" error and continue.

If your server is OK with this, you can always use RAW socket to send request then close it.

If you don't want to wait for response you can send data in another thread or simple use
WebClient.UploadStringAsync, but note that response always take place after request. Using another thread for request allows you to ignore response processing.

Take a look at this it may help.
public static void SetRequest(string mXml)
{
HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.CreateHttp("http://dork.com/service");
webRequest.Method = "POST";
webRequest.Headers["SOURCE"] = "WinApp";
// Decide your encoding here
//webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.ContentType = "text/xml; charset=utf-8";
// You should setContentLength
byte[] content = System.Text.Encoding.UTF8.GetBytes(mXml);
webRequest.ContentLength = content.Length;
var reqStream = await webRequest.GetRequestStreamAsync();
reqStream.Write(content, 0, content.Length);
var res = await httpRequest(webRequest);
}