各位前輩 請教教小弟 如何用 C# HttpWebRequest 登入某個網頁 因為我看回傳的網頁碼都是登入頁面的程式碼

這是網頁網址 http://ag1.amctqk418.cdbybj.com:88/

下面是小弟寫的

        string param = "loginName=" + loginname + "& loginPwd=" + loginpassword;
        byte[] bs = Encoding.ASCII.GetBytes(param);

        string URL = "http://ag1.amctqk418.cdbybj.com:88/";
          

            HttpWebRequest request = HttpWebRequest.Create(URL) as HttpWebRequest;
           
            
            request.Referer = "http://ag1.amctqk418.cdbybj.com:88/index.aspx";
            request.UserAgent = "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.81 Safari/537.36";
            request.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8";
            request.Headers.Set("Accept-Language", "zh-TW,zh;q=0.9,en-US;q=0.8,en;q=0.7");
            //request.Headers.Set("Accept-Encoding", "gzip, deflate");
            

            string result = null;
            request.Method = "POST";    // 方法
            request.KeepAlive = true; //是否保持連線
            request.ContentType = "application/x-www-form-urlencoded";              
            request.CookieContainer = session;

            using (Stream reqStream = request.GetRequestStream())
            {
                reqStream.Write(bs, 0, bs.Length);
                reqStream.Close();
            }

            using (WebResponse response = request.GetResponse())
        {
            StreamReader srr = new StreamReader(response.GetResponseStream(),System.Text.Encoding.UTF8);
            result = srr.ReadToEnd();
            
            cookie = request.CookieContainer.GetCookieHeader(request.RequestUri);
            srr.Close();               
        }


         Console.WriteLine(result);

我只有在reqStream.Write(bs, 0, bs.Length); 這裡面發現下面例外 我不知道有沒有影響