Question

private void LoginButton_Click(object sender, EventArgs e)
{
    try
    {
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(loginUrl);
        IAsyncResult result = request.BeginGetResponse(
            new AsyncCallback(DeleResponse), request);
    }
    catch(Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}

And here is the method which called to on button click event

private void DeleResponse(IAsyncResult result)
{
    byte[] PostData = Encoding.UTF8.GetBytes("username=" + userInp.Text + "&password=" + passInp.Text + extraLoginPostString);
    LoginButton.Text = "Logging in...";
    LoginButton.Enabled = false;
    HttpWebRequest request = (HttpWebRequest)result.AsyncState;
    request.Method = "Post";
    request.CookieContainer = authCookie;
    request.ContentType = "application/x-www-form-urlencoded";
    request.AllowAutoRedirect = false;
    postWriter = request.GetRequestStream();
    postWriter.Write(PostData, 0, PostData.Length);
    postWriter.Close();
        HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(result);
        string serverData = new StreamReader(response.GetResponseStream()).ReadToEnd();
    string loginValidateString = response.GetResponseHeader(loginValidateStringHolder);
    if (loginValidateString.Contains(LoggedKeyword))
    { 
            some process here:
        }
        else if( FAILKEYWORDCHECK HERE)
        {
            login page process here;
        }
    }

The problem is when I check this with fiddler I can see only following header properties.

Connection: Keep-Alive;
Host: www.example.com

What would be the reason that I can’t set properties in the request header?

Edit: Added synchronous request method which I already achieved without any errors.

 private void LoginButton_Click(object sender, EventArgs e)
    {
        try
        {
           LoginButton.Text = "Logging in...";
            LoginButton.Enabled = false;
            byte[] PostData = Encoding.UTF8.GetBytes("username=" + userInp.Text + "&password=" + passInp.Text + extraLoginPostString);
            request = (HttpWebRequest)WebRequest.Create(loginUrl);
            request.Method = "Post";
            request.CookieContainer = authCookie;
            request.ContentType = "application/x-www-form-urlencoded";
            request.AllowAutoRedirect = false;

            postWriter = request.GetRequestStream();
            postWriter.Write(PostData, 0, PostData.Length);
            postWriter.Close();

            response = (HttpWebResponse)request.GetResponse();

            string serverData = new StreamReader(response.GetResponseStream()).ReadToEnd();
            string loginValidateString = response.GetResponseHeader(loginValidateStringHolder);
            if (loginValidateString.Contains(LoggedKeyword))
            {
                MessageBox.Show("Logged in Successfully");

                foreach (Cookie cookieReader in response.Cookies)
                {
                    authCookie.Add(cookieReader);
                }
                Success method continues..
            }
            else if (loginValidateString.Contains(failedLogKeyword))
            {
                Failed process
            }
        }
        catch
        {
            Catchblock
        }
        }

Means, I just know how to set properties for normal requests.

Answer 1

You’re trying to set properties of the request when the response is available. You need to set the request properties before you make the request to the server – so you should be setting them in LoginButton_Click, not in the response handling code. Likewise you can’t use GetRequestStream in a callback for BeginGetResponse. Roughly speaking, you want:

• In the initial event handler:
  • Create the request
  • Set simple properties
  • Call BeginGetRequestStream
• In the callback handler for BeginGetRequestStream
  • Write out the body data
  • Call BeginGetResponse
• In the callback handler for BeginGetResponse
  • Handle the response data

Alternatively, unless you have to use the asynchronous calls, you could just create a separate thread and use the synchronous versions instead. Until the language support in C# 5, that would be simpler.