public class HttpWebResponseUtility{private static readonly string DefaultUserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";/// <summary>  /// 创建GET方式的HTTP请求  /// </summary>  /// <param name="url">请求的URL</param>  /// <param name="timeout">请求的超时时间</param>  /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>  /// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>  /// <returns></returns>  public static HttpWebResponse CreateGetHttpResponse(string url, int? timeout, string userAgent, CookieCollection cookies){if (string.IsNullOrEmpty(url)){throw new ArgumentNullException("url");}HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;request.Method = "GET";request.UserAgent = DefaultUserAgent;if (!string.IsNullOrEmpty(userAgent)){request.UserAgent = userAgent;}if (timeout.HasValue){request.Timeout = timeout.Value;}if (cookies != null){request.CookieContainer = new CookieContainer();request.CookieContainer.Add(cookies);}return request.GetResponse() as HttpWebResponse;}/// <summary>  /// 创建POST方式的HTTP请求  /// </summary>  /// <param name="url">请求的URL</param>  /// <param name="parameters">随同请求POST的参数名称及参数值字典</param>  /// <param name="timeout">请求的超时时间</param>  /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>  /// <param name="requestEncoding">发送HTTP请求时所用的编码</param>  /// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>  /// <returns></returns>  public static HttpWebResponse CreatePostHttpResponse(string url, IDictionary<string, string> parameters, int? timeout, string userAgent, Encoding requestEncoding, CookieCollection cookies){if (string.IsNullOrEmpty(url)){throw new ArgumentNullException("url");}if (requestEncoding == null){throw new ArgumentNullException("requestEncoding");}HttpWebRequest request = null;//如果是发送HTTPS请求  if (url.StartsWith("https", StringComparison.OrdinalIgnoreCase)){ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);request = WebRequest.Create(url) as HttpWebRequest;request.ProtocolVersion = HttpVersion.Version10;}else{request = WebRequest.Create(url) as HttpWebRequest;}request.Method = "POST";request.ContentType = "application/x-www-form-urlencoded";if (!string.IsNullOrEmpty(userAgent)){request.UserAgent = userAgent;}else{request.UserAgent = DefaultUserAgent;}if (timeout.HasValue){request.Timeout = timeout.Value;}if (cookies != null){request.CookieContainer = new CookieContainer();request.CookieContainer.Add(cookies);}//如果需要POST数据  if (!(parameters == null || parameters.Count == 0)){StringBuilder buffer = new StringBuilder();int i = 0;foreach (string key in parameters.Keys){if (i > 0){buffer.AppendFormat("&{0}={1}", key, parameters[key]);}else{buffer.AppendFormat("{0}={1}", key, parameters[key]);}i++;}byte[] data = requestEncoding.GetBytes(buffer.ToString());using (Stream stream = request.GetRequestStream()){stream.Write(data, 0, data.Length);}}return request.GetResponse() as HttpWebResponse;}private static bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors){return true; //总是接受  }}

 /// <summary>/// 模拟登录网站,并获取cookie/// </summary>public static void Request3(){string loginUrl = "博主某网站域名登录域名/login";string userName = "userName";string password = "password";string tagUrl = "博主某网站域名" + userName + "/token";            //设置编码方式Encoding encoding = Encoding.GetEncoding("gb2312");
            //此处设置Post请求的参数IDictionary<string, string> parameters = new Dictionary<string, string>();parameters.Add("参数1", "fa");parameters.Add("参数2", "fa");parameters.Add("参数3", tagUrl);parameters.Add("参数4", "0");parameters.Add("username", userName);parameters.Add("password", password);            //通过CreatePostHttpResponse方式请求登录的接口HttpWebResponse response = HttpWebResponseUtility.CreatePostHttpResponse(loginUrl, parameters, null, null, encoding, null);            //获取返回数据中的Cookie设置值。string cookieString = response.Headers["Set-Cookie"];//后续你想做的其他操作}

 public static void Request4(){string tagUrl = "登录后可访问的某些Get请求的URL地址";CookieCollection cookies = new CookieCollection();//如何从response.Headers["Set-Cookie"];中获取并设置CookieCollection的代码略，参照博文上一段var response = HttpWebResponseUtility.CreateGetHttpResponse(tagUrl, null, null, cookies);  }