byte[] bytes = Encoding.Default.GetBytes(_post);

                CookieContainer myCookieContainer = new CookieContainer();

                try

                {

                    //新建一个CookieContainer

                    HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(_loginurl);

                    //新建一个HttpWebRequest

                    myHttpWebRequest.ContentType = "application/x-www-form-urlencoded";

                    myHttpWebRequest.AllowAutoRedirect = false;

                    myHttpWebRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)";

                    myHttpWebRequest.Timeout = ;

                    myHttpWebRequest.KeepAlive = true;

                    myHttpWebRequest.ContentLength = bytes.Length;

                    myHttpWebRequest.Method = "POST";

                    myHttpWebRequest.CookieContainer = myCookieContainer;

                    //设置HttpWebRequest

                    Stream myRequestStream = myHttpWebRequest.GetRequestStream();

                    myRequestStream.Write(bytes, , bytes.Length);

                    myRequestStream.Close();

                    HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();

                    foreach (Cookie ck in myHttpWebResponse.Cookies)

                    {

                        myCookieContainer.Add(ck);

                    }

                    myHttpWebResponse.Close();

                }

                catch

                {

                    MessageBox.show("获取COOKIES失败！");

                    return;

                }