用webbrowser做的网站登陆程序，如何获取cookie并且保存在程序中 (IE8有效) ，用途嘛，你懂的。

 [DllImport("wininet.dll", CharSet = CharSet.Auto, SetLastError = true)]
        static extern bool InternetGetCookieEx(string pchURL, string pchCookieName, StringBuilder pchCookieData, ref int pcchCookieData, int dwFlags, object lpReserved);

 private static string GetCookieString(string url)
        {
            // Determine the size of the cookie   
            int datasize = 256;
            StringBuilder cookieData = new StringBuilder(datasize);

            if (!InternetGetCookieEx(url, null, cookieData, ref datasize, 0x00002000, null))
            {
                if (datasize < 0)
                    return null;

                // Allocate stringbuilder large enough to hold the cookie   
                cookieData = new StringBuilder(datasize);
                if (!InternetGetCookieEx(url, null, cookieData, ref datasize, 0x00002000, null))
                    return null;
            }
            return cookieData.ToString();
        }

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
                        request.Method = "GET";
                        request.Headers.Clear();
                        request.Headers[HttpRequestHeader.Cookie] = GetCookieString(url);
                        request.ContentType = "application/x-www-form-urlencoded";
                        request.KeepAlive = true;
                        request.AllowAutoRedirect = true;
                        HttpWebResponse httpResponse = (HttpWebResponse)request.GetResponse();
                        using (System.IO.Stream dataStream = httpResponse.GetResponseStream())
                        {
                            using (System.IO.StreamReader sr = new System.IO.StreamReader(dataStream, Encoding.GetEncoding("gb2312")))
                            {
                                html = sr.ReadToEnd();
                                sr.Close();
                            }
                        }
                        httpResponse.Close();