cookie 丢失的问题

string url = "http://xxxx/Login.aspx";

//第一步

CookieCollection cookie = new CookieCollection();

            HttpWebResponse HttpWResp = HttpWebResponseUtility.CreateGetHttpResponse(url, cookie, null, null);

            cookie = HttpWResp.Cookies;           

//第二步

  Dictionary<string, string> para = new Dictionary<string, string>();

            para.Add("UserID", "xxxx");

            para.Add("UserPwd", "xxxx");            

            HttpWebResponse HttpWResp2 = HttpWebResponseUtility.CreatePostHttpResponse(url, para, cookie);         

            HttpWResp2.Dispose();



///第三步

  url = "http://xxxx/List.aspx";

            HttpWebResponse HttpWResp3 = HttpWebResponseUtility.CreateGetHttpResponse(url, cookie, null, null);

            richTextBox1.Text = HttpWebResponseUtility.GetData(HttpWResp3);

            HttpWResp3.Dispose();

在第一步后能获取到cookie, 到第二步完成后cookie就消失了 这是为什么?

HttpWebResponseUtility 是 "周公" 的类 原文出处 "http://blog.csdn.net/zhoufoxcn"
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难道是被你清掉了？