HttpWebRequest非常奇怪的问题，高手进来帮我看看，救救小弟

Question

我用httpwebrequest 下载 "http://www2.baidu.com/?castk=e0d54av7eb5470266d589"
本来想得到通过HttpWebResponse.Headers.Get("Set-cookie");得到返回的cookie但是奇怪的是，在下载这个页面的时候，会自动下载以下两个url
http://fengchao.baidu.com/indexAction.do?uid=448186
http://fengchao.baidu.com/indexAction.do?uid=448186&userid=448186结果通过HttpWebResponse.Headers.Get("Set-cookie");得到的是
http://fengchao.baidu.com/indexAction.do?uid=448186&userid=448186
这个url返回的cookie，而不是http://www2.baidu.com/?castk=e0d54av7eb5470266d589
这个url返回的cookie；我该怎么解决才能得到http://www2.baidu.com/?castk=e0d54av7eb5470266d589
这个url返回的set-cookie参数各位大虾帮帮忙！！！小弟很急

Answer 1

源码如下：        public static string GetCookie(string URL,string curcookie, out string cookie)
        {
            HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(URL);            CookieContainer co = new CookieContainer();
            co.SetCookies(new Uri(URL), curcookie);
            myHttpWebRequest.CookieContainer = co;
               
            HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse(); 
            Stream receiveStream = myHttpWebResponse.GetResponseStream();
            Encoding encode = System.Text.Encoding.Default;
            StreamReader readStream = new StreamReader(receiveStream, encode);
            Char[] read = new Char[1024];    
            int count = readStream.Read( read, 0, 1024 );
            StringBuilder sb=new StringBuilder();
            while (count > 0) 
            {
                String str = new String(read, 0, count);
                sb.Append(str);
                count = readStream.Read(read, 0, 1024);
            }
            //string header=myHttpWebResponse.Headers.ToString();
            cookie = myHttpWebResponse.Headers.Get("Set-cookie");
            myHttpWebResponse.Close();
            readStream.Close();
            return sb.ToString();        }

Answer 2

查看了数据包后发现是因为
下载 "http://www2.baidu.com/?castk=e0d54av7eb5470266d589" 的时候，url有重定向，那么如何在重定向之前得到“set-cookie”值

Answer 3

查看了数据包后发现是因为
下载 "http://www2.baidu.com/?castk=e0d54av7eb5470266d589" 的时候，url有重定向，那么如何在重定向之前得到“set-cookie”值

Answer 4

我是这样获取的,这样cookie变量中就能完全取得了public string GetHtml(string url, byte[] data, Encoding encoding)
        {
            HttpWebResponse res = null;
            string strResult = "";            HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
            try
            {
                req.KeepAlive = true;
                req.Accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/msword, application/x-shockwave-flash, */*";
                req.Referer = referer;
                req.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Maxthon; .NET CLR 2.0.50727)";
                //设置cookie
                reqcookie.Add(cookie);
                req.CookieContainer = reqcookie;
                //req.CookieContainer.Add(cookie);                if (proxy != "")
                {
                    WebProxy proxys = new WebProxy();
                    proxys.Address = new Uri("http://" + this.proxy);
                    req.Proxy = proxys;
                }
                else
                {
                    req.Proxy = null;
                }                //byte[] data = encoding.GetBytes(postdata);
                if (data.Length > 0)
                {
                    req.Method = "POST";
                    req.ContentType = "application/x-www-form-urlencoded";
                    req.ContentLength = data.Length;
                    using (System.IO.Stream sw = req.GetRequestStream())
                    {
                        try
                        {                            sw.Write(data, 0, data.Length);
                        }
                        catch
                        {
                            strResult = "";
                            return strResult;
                        }
                        finally
                        {                        }
                    }
                }
                try
                {
                    HttpWebResponse response = null;
                    System.IO.StreamReader sr = null;                    try
                    {                        response = (HttpWebResponse)req.GetResponse();
                        foreach (Cookie c in response.Cookies)
                        {
                            Console.WriteLine("Name: {0}", c.Name);
                            Console.WriteLine("Value: {0}", c.Value);
                            Console.WriteLine("Domain: {0}", c.Domain);
                            Console.WriteLine("Expires: {0}", c.Expires);
                        }
                        Console.WriteLine("============================================");
                        this.cookie.Add(response.Cookies);
                        sr = new System.IO.StreamReader(response.GetResponseStream(), encoding);                        strResult = sr.ReadToEnd();                    }
                    catch (WebException webex)
                    {
                        if (webex.Status == WebExceptionStatus.KeepAliveFailure)
                        {
                            strResult = "";
                            return strResult;
                        }
                        else
                        {
                            strResult = "";
                            return strResult;
                        }
                    }
                    catch (System.Exception ex)
                    {
                        strResult = ex.Message;
                        return strResult;
                    }
                    finally
                    {
                        if (sr != null) { sr.Close(); }
                        if (response != null) { response.Close(); }
                        response = null;
                        req = null;
                    }
                    return strResult;
                }
                catch
                {
                    return "";
                }
            }
            catch
            {
                return "";
            }
        }

Answer 5

不好意思,没有看清楚你的问题,你这样的情况最好不要用HttpWebResponse,因为HttpWebResponse会自动重定向,你要获取的是第一个页面的数据,用TcpClient就可以了,用TcpClient发送HTTP包就可以用返回的数据中从取得Cookie的数据,
模拟发送的包如下
GET /?action=logout&u=http%3A%2F%2Fcas.baidu.com%2F%3Ftpl%3Dwww2 HTTP/1.1Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/msword, application/x-shockwave-flash, */*User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Maxthon; .NET CLR 2.0.50727)Host: cas.baidu.com返回的数据包如下
HTTP/1.1 302 FoundDate: Sat, 18 Jul 2009 03:13:09 GMTServer: Apache/2.2.9 (Unix) mod_ssl/2.2.9 OpenSSL/0.9.7a DAV/2 PHP/5.2.4X-Powered-By: PHP/5.2.4Expires: Thu, 19 Nov 1981 08:52:00 GMTCache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0Pragma: no-cacheLocation: http://cas.baidu.com/?tpl=www2Content-Length: 0Connection: closeContent-Type: text/html

Answer 6

或者使HttpWebRequest不重定向就可以了
请求.AllowAutoRedirect   =   false;