Session cookies - CookieContainer on stack rather than heap causing issue - session

Question

I've had a look here
C# WebRequest using Cookies
Multiple WebRequest in same session
Reuse Connection with HttpWebRequest in C#
C# keep session id over httpwebrequest
And that's what I'm doing except I wish to store my CookieContainer as a member (named session_cookie) in my class called connector. My problem is that if I use a temporary object in my code then the cookies work fine:
CookieContainer t = new CookieContainer();
HTTPReq = (HttpWebRequest)WebRequest.Create(scriptURL);
HTTPReq.CookieContainer = t;
But if I use
HTTPReq = (HttpWebRequest)WebRequest.Create(scriptURL);
HTTPReq.CookieContainer = session_cookie;
Then it doesn't work! I cannot figure out why
Here is the connector class code:
public class Connector
{
public CookieContainer session_cookie;
private string session_id;
private HttpWebRequest HTTPReq;
private HttpWebResponse Response;
//Session oriented connection
public string serverRequest(string scriptURL, string payLoad)
{
try
{
HTTPReq = (HttpWebRequest)WebRequest.Create(scriptURL);
HTTPReq.CookieContainer = session_cookie;
HTTPReq.Method = "POST";
//Data arguments
byte[] byteArray = Encoding.UTF8.GetBytes(payLoad);
HTTPReq.ContentType = "application/x-www-form-urlencoded";
HTTPReq.ContentLength = byteArray.Length;
//Get the stream to write into
Stream dataStream = HTTPReq.GetRequestStream();
dataStream.Write(byteArray, 0, byteArray.Length);
dataStream.Close();
Response = (HttpWebResponse)HTTPReq.GetResponse();
Encoding enc = Encoding.GetEncoding(1252); // Western latin alphabet (windows default)
//Get the repsonse from the server
StreamReader ResponseStream = new StreamReader(Response.GetResponseStream(), enc);
string response = ResponseStream.ReadToEnd().Trim();
Response.Close();
ResponseStream.Close();
return response;
}
catch (WebException ex)
{
Console.WriteLine(ex.ToString());
return null;
}
}
}
Any ideas?

Answer 1

You are missing a constructor for your Connector class which needs to initialize your CookieContainer property. You should also use a CookieCollection for capturing the cookies from the response and sending to the next request. Something like this should work:
public class Connector
{
public CookieContainer session_cookie;
private CookieCollection cookies;
private string session_id;
private HttpWebRequest HTTPReq;
private HttpWebResponse Response;
public Connector()
{
session_cookie = new CookieContainer();
cookies = new CookieCollection();
}
//Session oriented connection
public string serverRequest(string scriptURL, string payLoad)
{
try
{
HTTPReq = (HttpWebRequest)WebRequest.Create(scriptURL);
HTTPReq.CookieContainer = session_cookie;
HTTPReq.CookieContainer.Add(cookies);
HTTPReq.Method = "POST";
//Data arguments
byte[] byteArray = Encoding.UTF8.GetBytes(payLoad);
HTTPReq.ContentType = "application/x-www-form-urlencoded";
HTTPReq.ContentLength = byteArray.Length;
//Get the stream to write into
Stream dataStream = HTTPReq.GetRequestStream();
dataStream.Write(byteArray, 0, byteArray.Length);
dataStream.Close();
Response = (HttpWebResponse)HTTPReq.GetResponse();
cookies = Response.Cookies; // capture cookies from response for next request
Encoding enc = Encoding.GetEncoding(1252); // Western latin alphabet (windows default)
//Get the repsonse from the server
StreamReader ResponseStream = new StreamReader(Response.GetResponseStream(), enc);
string response = ResponseStream.ReadToEnd().Trim();
Response.Close();
ResponseStream.Close();
return response;
}
catch (WebException ex)
{
Console.WriteLine(ex.ToString());
return null;
}
}
}