using System.Text;

using System.Net;

using System.IO;

using System.Text.RegularExpressions;

using System.Security.Cryptography.X509Certificates;

using System.Net.Security;

namespace WebRequestTest

{

    /// <summary>

    /// 动态类，每个实例使用单独session

    /// </summary>

    public class HttpHelperNew

    {

       public CookieContainer cookie = new CookieContainer();

        /// <summary>

        /// post请求返回html

        /// </summary>

        /// <param name="Url"></param>

        /// <param name="postDataStr"></param>

        /// <returns></returns>

        public string HttpPost(string Url, string postDataStr)

        {

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);

            //request.AllowAutoRedirect = false; //禁止自动重定向

            request.Method = "POST";

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

            request.ContentLength = Encoding.UTF8.GetByteCount(postDataStr);

            request.CookieContainer = cookie; //cookie信息由CookieContainer自行维护

            Stream myRequestStream = request.GetRequestStream();

            StreamWriter myStreamWriter = new StreamWriter(myRequestStream, Encoding.GetEncoding("gb2312"));

            myStreamWriter.Write(postDataStr);

            myStreamWriter.Close();

            HttpWebResponse response = null;

            try

            {

                this.SetCertificatePolicy();

                response = (HttpWebResponse)request.GetResponse();

            }

            catch (System.Exception ex)

            {

            }

            //获取重定向地址

            //string url1 = response.Headers["Location"];

            if (response !=null)

            {

                Stream myResponseStream = response.GetResponseStream();

                StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));

                string retString = myStreamReader.ReadToEnd();

                myStreamReader.Close();

                myResponseStream.Close();

                return retString;

            }

            else

            {

                return "error"; //post请求返回为空

            }

        }

        /// <summary>

        /// get请求获取返回的html

        /// </summary>

        /// <param name="Url"></param>

        /// <param name="postDataStr"></param>

        /// <returns></returns>

        public string HttpGet(string Url, string Querydata)

        {

           

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url + (Querydata == "" ? "" : "?") + Querydata);

            request.Method = "GET";

            request.ContentType = "text/html;charset=UTF-8";

            request.CookieContainer = cookie;

            this.SetCertificatePolicy();

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();

           // response.Cookies = cookie.GetCookies(response.ResponseUri);

            Stream myResponseStream = response.GetResponseStream();

            StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));

            string retString = myStreamReader.ReadToEnd();

            myStreamReader.Close();

            myResponseStream.Close();

            return retString;

        }

        /// <summary>

        /// 获得响应中的图像

        /// </summary>

        /// <param name="url"></param>

        /// <returns></returns>

        public Stream GetResponseImage(string url)

        {

            Stream resst = null;

            try

            {

                HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);

                req.KeepAlive = true;

                req.Method = "GET";

                req.AllowAutoRedirect = true;

                req.CookieContainer = cookie;

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

                req.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";

                req.Timeout = 50000;

                Encoding myEncoding = Encoding.GetEncoding("UTF-8");

                this.SetCertificatePolicy();

                HttpWebResponse res = (HttpWebResponse)req.GetResponse();

                resst = res.GetResponseStream();

                return resst;

            }

            catch

            {

                return null;

            }

        }

        /// <summary>

        /// 正则获取匹配的第一个值

        /// </summary>

        /// <param name="html"></param>

        /// <param name="pattern"></param>

        /// <returns></returns>

        public string getStringByRegex(string html,string pattern)

        {

            Regex re = new Regex(pattern, RegexOptions.IgnoreCase);

            MatchCollection matchs = re.Matches(html);

            if (matchs.Count > 0)

            {

                return matchs[0].Groups[1].Value;

            }

            else

                return "";

        }

        /// <summary>

        /// 正则验证返回的response是否正确

        /// </summary>

        /// <param name="html"></param>

        /// <param name="pattern"></param>

        /// <returns></returns>

        public bool verifyResponseHtml(string html ,string pattern)

        {

            Regex re = new Regex(pattern);

            return re.IsMatch(html);

        }

        //注册证书验证回调事件，在请求之前注册

        private void SetCertificatePolicy()

        {

            ServicePointManager.ServerCertificateValidationCallback

                       += RemoteCertificateValidate;

        }

        /// <summary>  

        /// 远程证书验证，固定返回true

        /// </summary>  

        private static bool RemoteCertificateValidate(object sender, X509Certificate cert,

            X509Chain chain, SslPolicyErrors error)

        {

            return true;

        }  

    }

}