爬虫 HttpHelper

 /// <summary>  
/// 类说明：HttpHelper类，用来实现Http访问，Post或者Get方式的，直接访问，带Cookie的，带证书的等方式，可以设置代理  
/// 重要提示：请不要自行修改本类，如果因为你自己修改后将无法升级到新版本。如果确实有什么问题请到官方网站提建议，  
/// 我们一定会及时修改  
/// 编码日期：2011-09-20  
/// 编 码 人：苏飞  
/// 联系方式：361983679    
/// 官方网址：http://www.sufeinet.com/thread-3-1-1.html  
/// 修改日期：2016-12-05  
/// 版 本 号：1.7  
/// </summary>  
using System;  
using System.Collections.Generic;  
using System.Text;  
using System.Net;  
using System.IO;  
using System.Text.RegularExpressions;  
using System.IO.Compression;  
using System.Security.Cryptography.X509Certificates;  
using System.Net.Security;  
using System.Linq;  
using System.Net.Cache;  
  
namespace DotNet4.Utilities  
{  
    /// <summary>  
    /// Http连接操作帮助类  
    /// </summary>  
    public class HttpHelper  
    {  
        #region 预定义方变量  
        //默认的编码  
        private Encoding encoding = Encoding.Default;  
        //Post数据编码  
        private Encoding postencoding = Encoding.Default;  
        //HttpWebRequest对象用来发起请求  
        private HttpWebRequest request = null;  
        //获取影响流的数据对象  
        private HttpWebResponse response = null;  
        //设置本地的出口ip和端口  
        private IPEndPoint _IPEndPoint = null;  
        #endregion  
 
        #region Public  
  
        /// <summary>  
        /// 根据相传入的数据，得到相应页面数据  
        /// </summary>  
        /// <param name="item">参数类对象</param>  
        /// <returns>返回HttpResult类型</returns>  
        public HttpResult GetHtml(HttpItem item)  
        {  
            //返回参数  
            HttpResult result = new HttpResult();  
            try  
            {  
                //准备参数  
                SetRequest(item);  
            }  
            catch (Exception ex)  
            {  
                //配置参数时出错  
                return new HttpResult() { Cookie = string.Empty, Header = null, Html = ex.Message, StatusDescription = "配置参数时出错：" + ex.Message };  
            }  
            try  
            {  
                //请求数据  
                using (response = (HttpWebResponse)request.GetResponse())  
                {  
                    GetData(item, result);  
                }  
            }  
            catch (WebException ex)  
            {  
                if (ex.Response != null)  
                {  
                    using (response = (HttpWebResponse)ex.Response)  
                    {  
                        GetData(item, result);  
                    }  
                }  
                else  
                {  
                    result.Html = ex.Message;  
                }  
            }  
            catch (Exception ex)  
            {  
                result.Html = ex.Message;  
            }  
            if (item.IsToLower) result.Html = result.Html.ToLower();  
            return result;  
        }  
        #endregion  
 
        #region GetData  
  
        /// <summary>  
        /// 获取数据的并解析的方法  
        /// </summary>  
        /// <param name="item"></param>  
        /// <param name="result"></param>  
        private void GetData(HttpItem item, HttpResult result)  
        {  
            if (response == null)  
            {  
                return;  
            }  
            #region base  
            //获取StatusCode  
            result.StatusCode = response.StatusCode;  
            //获取StatusDescription  
            result.StatusDescription = response.StatusDescription;  
            //获取Headers  
            result.Header = response.Headers;  
            //获取最后访问的URl  
            result.ResponseUri = response.ResponseUri.ToString();  
            //获取CookieCollection  
            if (response.Cookies != null) result.CookieCollection = response.Cookies;  
            //获取set-cookie  
            if (response.Headers["set-cookie"] != null) result.Cookie = response.Headers["set-cookie"];  
            #endregion  
 
            #region byte  
            //处理网页Byte  
            byte[] ResponseByte = GetByte();  
            #endregion  
 
            #region Html  
            if (ResponseByte != null && ResponseByte.Length > 0)  
            {  
                //设置编码  
                SetEncoding(item, result, ResponseByte);  
                //得到返回的HTML  
                result.Html = encoding.GetString(ResponseByte);  
            }  
            else  
            {  
                //没有返回任何Html代码  
                result.Html = string.Empty;  
            }  
            #endregion  
        }  
        /// <summary>  
        /// 设置编码  
        /// </summary>  
        /// <param name="item">HttpItem</param>  
        /// <param name="result">HttpResult</param>  
        /// <param name="ResponseByte">byte[]</param>  
        private void SetEncoding(HttpItem item, HttpResult result, byte[] ResponseByte)  
        {  
            //是否返回Byte类型数据  
            if (item.ResultType == ResultType.Byte) result.ResultByte = ResponseByte;  
            //从这里开始我们要无视编码了  
            if (encoding == null)  
            {  
                Match meta = Regex.Match(Encoding.Default.GetString(ResponseByte), "<meta[^<]*charset=([^<]*)[\"']", RegexOptions.IgnoreCase);  
                string c = string.Empty;  
                if (meta != null && meta.Groups.Count > 0)  
                {  
                    c = meta.Groups[1].Value.ToLower().Trim();  
                }  
                if (c.Length > 2)  
                {  
                    try  
                    {  
                        encoding = Encoding.GetEncoding(c.Replace("\"", string.Empty).Replace("'", "").Replace(";", "").Replace("iso-8859-1", "gbk").Trim());  
                    }  
                    catch  
                    {  
                        if (string.IsNullOrEmpty(response.CharacterSet))  
                        {  
                            encoding = Encoding.UTF8;  
                        }  
                        else  
                        {  
                            encoding = Encoding.GetEncoding(response.CharacterSet);  
                        }  
                    }  
                }  
                else  
                {  
                    if (string.IsNullOrEmpty(response.CharacterSet))  
                    {  
                        encoding = Encoding.UTF8;  
                    }  
                    else  
                    {  
                        encoding = Encoding.GetEncoding(response.CharacterSet);  
                    }  
                }  
            }  
        }  
        /// <summary>  
        /// 提取网页Byte  
        /// </summary>  
        /// <returns></returns>  
        private byte[] GetByte()  
        {  
            byte[] ResponseByte = null;  
            using (MemoryStream _stream = new MemoryStream())  
            {  
                //GZIIP处理  
                if (response.ContentEncoding != null && response.ContentEncoding.Equals("gzip", StringComparison.InvariantCultureIgnoreCase))  
                {  
                    //开始读取流并设置编码方式  
                    new GZipStream(response.GetResponseStream(), CompressionMode.Decompress).CopyTo(_stream, 10240);  
                }  
                else  
                {  
                    //开始读取流并设置编码方式  
                    response.GetResponseStream().CopyTo(_stream, 10240);  
                }  
                //获取Byte  
                ResponseByte = _stream.ToArray();  
            }  
            return ResponseByte;  
        }  
 
 
        #endregion  
 
        #region SetRequest  
  
        /// <summary>  
        /// 为请求准备参数  
        /// </summary>  
        ///<param name="item">参数列表</param>  
        private void SetRequest(HttpItem item)  
        {  
  
            // 验证证书  
            SetCer(item);  
            if (item.IPEndPoint != null)  
            {  
                _IPEndPoint = item.IPEndPoint;  
                //设置本地的出口ip和端口  
                request.ServicePoint.BindIPEndPointDelegate = new BindIPEndPoint(BindIPEndPointCallback);  
            }  
            //设置Header参数  
            if (item.Header != null && item.Header.Count > 0) foreach (string key in item.Header.AllKeys)  
                {  
                    request.Headers.Add(key, item.Header[key]);  
                }  
            // 设置代理  
            SetProxy(item);  
            if (item.ProtocolVersion != null) request.ProtocolVersion = item.ProtocolVersion;  
            request.ServicePoint.Expect100Continue = item.Expect100Continue;  
            //请求方式Get或者Post  
            request.Method = item.Method;  
            request.Timeout = item.Timeout;  
            request.KeepAlive = item.KeepAlive;  
            request.ReadWriteTimeout = item.ReadWriteTimeout;  
            if (!string.IsNullOrWhiteSpace(item.Host))  
            {  
                request.Host = item.Host;  
            }  
            if (item.IfModifiedSince != null) request.IfModifiedSince = Convert.ToDateTime(item.IfModifiedSince);  
            //Accept  
            request.Accept = item.Accept;  
            //ContentType返回类型  
            request.ContentType = item.ContentType;  
            //UserAgent客户端的访问类型，包括浏览器版本和操作系统信息  
            request.UserAgent = item.UserAgent;  
            // 编码  
            encoding = item.Encoding;  
            //设置安全凭证  
            request.Credentials = item.ICredentials;  
            //设置Cookie  
            SetCookie(item);  
            //来源地址  
            request.Referer = item.Referer;  
            //是否执行跳转功能  
            request.AllowAutoRedirect = item.Allowautoredirect;  
            if (item.MaximumAutomaticRedirections > 0)  
            {  
                request.MaximumAutomaticRedirections = item.MaximumAutomaticRedirections;  
            }  
            //设置Post数据  
            SetPostData(item);  
            //设置最大连接  
            if (item.Connectionlimit > 0) request.ServicePoint.ConnectionLimit = item.Connectionlimit;  
        }  
        /// <summary>  
        /// 设置证书  
        /// </summary>  
        /// <param name="item"></param>  
        private void SetCer(HttpItem item)  
        {  
            if (!string.IsNullOrWhiteSpace(item.CerPath))  
            {  
                //这一句一定要写在创建连接的前面。使用回调的方法进行证书验证。  
                ServicePointManager.ServerCertificateValidationCallback = new System.Net.Security.RemoteCertificateValidationCallback(CheckValidationResult);  
                //初始化对像，并设置请求的URL地址  
                request = (HttpWebRequest)WebRequest.Create(item.URL);  
                SetCerList(item);  
                //将证书添加到请求里  
                request.ClientCertificates.Add(new X509Certificate(item.CerPath));  
            }  
            else  
            {  
                //初始化对像，并设置请求的URL地址  
                request = (HttpWebRequest)WebRequest.Create(item.URL);  
                SetCerList(item);  
            }  
        }  
        /// <summary>  
        /// 设置多个证书  
        /// </summary>  
        /// <param name="item"></param>  
        private void SetCerList(HttpItem item)  
        {  
            if (item.ClentCertificates != null && item.ClentCertificates.Count > 0)  
            {  
                foreach (X509Certificate c in item.ClentCertificates)  
                {  
                    request.ClientCertificates.Add(c);  
                }  
            }  
        }  
        /// <summary>  
        /// 设置Cookie  
        /// </summary>  
        /// <param name="item">Http参数</param>  
        private void SetCookie(HttpItem item)  
        {  
            if (!string.IsNullOrEmpty(item.Cookie)) request.Headers[HttpRequestHeader.Cookie] = item.Cookie;  
            //设置CookieCollection  
            if (item.ResultCookieType == ResultCookieType.CookieCollection)  
            {  
                request.CookieContainer = new CookieContainer();  
                if (item.CookieCollection != null && item.CookieCollection.Count > 0)  
                    request.CookieContainer.Add(item.CookieCollection);  
            }  
        }  
        /// <summary>  
        /// 设置Post数据  
        /// </summary>  
        /// <param name="item">Http参数</param>  
        private void SetPostData(HttpItem item)  
        {  
            //验证在得到结果时是否有传入数据  
            if (!request.Method.Trim().ToLower().Contains("get"))  
            {  
                if (item.PostEncoding != null)  
                {  
                    postencoding = item.PostEncoding;  
                }  
                byte[] buffer = null;  
                //写入Byte类型  
                if (item.PostDataType == PostDataType.Byte && item.PostdataByte != null && item.PostdataByte.Length > 0)  
                {  
                    //验证在得到结果时是否有传入数据  
                    buffer = item.PostdataByte;  
                }//写入文件  
                else if (item.PostDataType == PostDataType.FilePath && !string.IsNullOrWhiteSpace(item.Postdata))  
                {  
                    StreamReader r = new StreamReader(item.Postdata, postencoding);  
                    buffer = postencoding.GetBytes(r.ReadToEnd());  
                    r.Close();  
                } //写入字符串  
                else if (!string.IsNullOrWhiteSpace(item.Postdata))  
                {  
                    buffer = postencoding.GetBytes(item.Postdata);  
                }  
                if (buffer != null)  
                {  
                    request.ContentLength = buffer.Length;  
                    request.GetRequestStream().Write(buffer, 0, buffer.Length);  
                }  
            }  
        }  
        /// <summary>  
        /// 设置代理  
        /// </summary>  
        /// <param name="item">参数对象</param>  
        private void SetProxy(HttpItem item)  
        {  
            bool isIeProxy = false;  
            if (!string.IsNullOrWhiteSpace(item.ProxyIp))  
            {  
                isIeProxy = item.ProxyIp.ToLower().Contains("ieproxy");  
            }  
            if (!string.IsNullOrWhiteSpace(item.ProxyIp) && !isIeProxy)  
            {  
                //设置代理服务器  
                if (item.ProxyIp.Contains(":"))  
                {  
                    string[] plist = item.ProxyIp.Split(':');  
                    WebProxy myProxy = new WebProxy(plist[0].Trim(), Convert.ToInt32(plist[1].Trim()));  
                    //建议连接  
                    myProxy.Credentials = new NetworkCredential(item.ProxyUserName, item.ProxyPwd);  
                    //给当前请求对象  
                    request.Proxy = myProxy;  
                }  
                else  
                {  
                    WebProxy myProxy = new WebProxy(item.ProxyIp, false);  
                    //建议连接  
                    myProxy.Credentials = new NetworkCredential(item.ProxyUserName, item.ProxyPwd);  
                    //给当前请求对象  
                    request.Proxy = myProxy;  
                }  
            }  
            else if (isIeProxy)  
            {  
                //设置为IE代理  
            }  
            else  
            {  
                request.Proxy = item.WebProxy;  
            }  
        }  
 
 
        #endregion  
 
        #region private main  
        /// <summary>  
        /// 回调验证证书问题  
        /// </summary>  
        /// <param name="sender">流对象</param>  
        /// <param name="certificate">证书</param>  
        /// <param name="chain">X509Chain</param>  
        /// <param name="errors">SslPolicyErrors</param>  
        /// <returns>bool</returns>  
        private bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors) { return true; }  
  
        /// <summary>  
        /// 通过设置这个属性，可以在发出连接的时候绑定客户端发出连接所使用的IP地址。   
        /// </summary>  
        /// <param name="servicePoint"></param>  
        /// <param name="remoteEndPoint"></param>  
        /// <param name="retryCount"></param>  
        /// <returns></returns>  
        private IPEndPoint BindIPEndPointCallback(ServicePoint servicePoint, IPEndPoint remoteEndPoint, int retryCount)  
        {  
            return _IPEndPoint;//端口号  
        }  
        #endregion  
    }  
 
    #region public calss  
    /// <summary>  
    /// Http请求参考类  
    /// </summary>  
    public class HttpItem  
    {  
        /// <summary>  
        /// 请求URL必须填写  
        /// </summary>  
        public string URL { get; set; }  
        string _Method = "GET";  
        /// <summary>  
        /// 请求方式默认为GET方式,当为POST方式时必须设置Postdata的值  
        /// </summary>  
        public string Method  
        {  
            get { return _Method; }  
            set { _Method = value; }  
        }  
        int _Timeout = 100000;  
        /// <summary>  
        /// 默认请求超时时间  
        /// </summary>  
        public int Timeout  
        {  
            get { return _Timeout; }  
            set { _Timeout = value; }  
        }  
        int _ReadWriteTimeout = 30000;  
        /// <summary>  
        /// 默认写入Post数据超时间  
        /// </summary>  
        public int ReadWriteTimeout  
        {  
            get { return _ReadWriteTimeout; }  
            set { _ReadWriteTimeout = value; }  
        }  
        /// <summary>  
        /// 设置Host的标头信息  
        /// </summary>  
        public string Host { get; set; }  
        Boolean _KeepAlive = true;  
        /// <summary>  
        ///  获取或设置一个值，该值指示是否与 Internet 资源建立持久性连接默认为true。  
        /// </summary>  
        public Boolean KeepAlive  
        {  
            get { return _KeepAlive; }  
            set { _KeepAlive = value; }  
        }  
        string _Accept = "text/html, application/xhtml+xml, */*";  
        /// <summary>  
        /// 请求标头值 默认为text/html, application/xhtml+xml, */*  
        /// </summary>  
        public string Accept  
        {  
            get { return _Accept; }  
            set { _Accept = value; }  
        }  
        string _ContentType = "text/html";  
        /// <summary>  
        /// 请求返回类型默认 text/html  
        /// </summary>  
        public string ContentType  
        {  
            get { return _ContentType; }  
            set { _ContentType = value; }  
        }  
        string _UserAgent = "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)";  
        /// <summary>  
        /// 客户端访问信息默认Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)  
        /// </summary>  
        public string UserAgent  
        {  
            get { return _UserAgent; }  
            set { _UserAgent = value; }  
        }  
        /// <summary>  
        /// 返回数据编码默认为NUll,可以自动识别,一般为utf-8,gbk,gb2312  
        /// </summary>  
        public Encoding Encoding { get; set; }  
        private PostDataType _PostDataType = PostDataType.String;  
        /// <summary>  
        /// Post的数据类型  
        /// </summary>  
        public PostDataType PostDataType  
        {  
            get { return _PostDataType; }  
            set { _PostDataType = value; }  
        }  
        /// <summary>  
        /// Post请求时要发送的字符串Post数据  
        /// </summary>  
        public string Postdata { get; set; }  
        /// <summary>  
        /// Post请求时要发送的Byte类型的Post数据  
        /// </summary>  
        public byte[] PostdataByte { get; set; }  
        /// <summary>  
        /// Cookie对象集合  
        /// </summary>  
        public CookieCollection CookieCollection { get; set; }  
        /// <summary>  
        /// 请求时的Cookie  
        /// </summary>  
        public string Cookie { get; set; }  
        /// <summary>  
        /// 来源地址，上次访问地址  
        /// </summary>  
        public string Referer { get; set; }  
        /// <summary>  
        /// 证书绝对路径  
        /// </summary>  
        public string CerPath { get; set; }  
        /// <summary>  
        /// 设置代理对象，不想使用IE默认配置就设置为Null，而且不要设置ProxyIp  
        /// </summary>  
        public WebProxy WebProxy { get; set; }  
        private Boolean isToLower = false;  
        /// <summary>  
        /// 是否设置为全文小写，默认为不转化  
        /// </summary>  
        public Boolean IsToLower  
        {  
            get { return isToLower; }  
            set { isToLower = value; }  
        }  
        private Boolean allowautoredirect = false;  
        /// <summary>  
        /// 支持跳转页面，查询结果将是跳转后的页面，默认是不跳转  
        /// </summary>  
        public Boolean Allowautoredirect  
        {  
            get { return allowautoredirect; }  
            set { allowautoredirect = value; }  
        }  
        private int connectionlimit = 1024;  
        /// <summary>  
        /// 最大连接数  
        /// </summary>  
        public int Connectionlimit  
        {  
            get { return connectionlimit; }  
            set { connectionlimit = value; }  
        }  
        /// <summary>  
        /// 代理Proxy 服务器用户名  
        /// </summary>  
        public string ProxyUserName { get; set; }  
        /// <summary>  
        /// 代理 服务器密码  
        /// </summary>  
        public string ProxyPwd { get; set; }  
        /// <summary>  
        /// 代理 服务IP,如果要使用IE代理就设置为ieproxy  
        /// </summary>  
        public string ProxyIp { get; set; }  
        private ResultType resulttype = ResultType.String;  
        /// <summary>  
        /// 设置返回类型String和Byte  
        /// </summary>  
        public ResultType ResultType  
        {  
            get { return resulttype; }  
            set { resulttype = value; }  
        }  
        private WebHeaderCollection header = new WebHeaderCollection();  
        /// <summary>  
        /// header对象  
        /// </summary>  
        public WebHeaderCollection Header  
        {  
            get { return header; }  
            set { header = value; }  
        }  
        /// <summary>  
        //     获取或设置用于请求的 HTTP 版本。返回结果:用于请求的 HTTP 版本。默认为 System.Net.HttpVersion.Version11。  
        /// </summary>  
        public Version ProtocolVersion { get; set; }  
        private Boolean _expect100continue = false;  
        /// <summary>  
        ///  获取或设置一个 System.Boolean 值，该值确定是否使用 100-Continue 行为。如果 POST 请求需要 100-Continue 响应，则为 true；否则为 false。默认值为 true。  
        /// </summary>  
        public Boolean Expect100Continue  
        {  
            get { return _expect100continue; }  
            set { _expect100continue = value; }  
        }  
        /// <summary>  
        /// 设置509证书集合  
        /// </summary>  
        public X509CertificateCollection ClentCertificates { get; set; }  
        /// <summary>  
        /// 设置或获取Post参数编码,默认的为Default编码  
        /// </summary>  
        public Encoding PostEncoding { get; set; }  
        private ResultCookieType _ResultCookieType = ResultCookieType.String;  
        /// <summary>  
        /// Cookie返回类型,默认的是只返回字符串类型  
        /// </summary>  
        public ResultCookieType ResultCookieType  
        {  
            get { return _ResultCookieType; }  
            set { _ResultCookieType = value; }  
        }  
        private ICredentials _ICredentials = CredentialCache.DefaultCredentials;  
        /// <summary>  
        /// 获取或设置请求的身份验证信息。  
        /// </summary>  
        public ICredentials ICredentials  
        {  
            get { return _ICredentials; }  
            set { _ICredentials = value; }  
        }  
        /// <summary>  
        /// 设置请求将跟随的重定向的最大数目  
        /// </summary>  
        public int MaximumAutomaticRedirections { get; set; }  
        private DateTime? _IfModifiedSince = null;  
        /// <summary>  
        /// 获取和设置IfModifiedSince，默认为当前日期和时间  
        /// </summary>  
        public DateTime? IfModifiedSince  
        {  
            get { return _IfModifiedSince; }  
            set { _IfModifiedSince = value; }  
        }  
        #region ip-port  
        private IPEndPoint _IPEndPoint = null;  
        /// <summary>  
        /// 设置本地的出口ip和端口  
        /// </summary>]  
        /// <example>  
        ///item.IPEndPoint = new IPEndPoint(IPAddress.Parse("192.168.1.1"),80);  
        /// </example>  
        public IPEndPoint IPEndPoint  
        {  
            get { return _IPEndPoint; }  
            set { _IPEndPoint = value; }  
        }  
        #endregion  
    }  
    /// <summary>  
    /// Http返回参数类  
    /// </summary>  
    public class HttpResult  
    {  
        /// <summary>  
        /// Http请求返回的Cookie  
        /// </summary>  
        public string Cookie { get; set; }  
        /// <summary>  
        /// Cookie对象集合  
        /// </summary>  
        public CookieCollection CookieCollection { get; set; }  
        private string _html = string.Empty;  
        /// <summary>  
        /// 返回的String类型数据 只有ResultType.String时才返回数据，其它情况为空  
        /// </summary>  
        public string Html  
        {  
            get { return _html; }  
            set { _html = value; }  
        }  
        /// <summary>  
        /// 返回的Byte数组 只有ResultType.Byte时才返回数据，其它情况为空  
        /// </summary>  
        public byte[] ResultByte { get; set; }  
        /// <summary>  
        /// header对象  
        /// </summary>  
        public WebHeaderCollection Header { get; set; }  
        /// <summary>  
        /// 返回状态说明  
        /// </summary>  
        public string StatusDescription { get; set; }  
        /// <summary>  
        /// 返回状态码,默认为OK  
        /// </summary>  
        public HttpStatusCode StatusCode { get; set; }  
        /// <summary>  
        /// 最后访问的URl  
        /// </summary>  
        public string ResponseUri { get; set; }  
        /// <summary>  
        /// 获取重定向的URl  
        /// </summary>  
        public string RedirectUrl  
        {  
            get  
            {  
                try  
                {  
                    if (Header != null && Header.Count > 0)  
                    {  
                        if (Header.AllKeys.Any(k => k.ToLower().Contains("location")))  
                        {  
                            string baseurl = Header["location"].ToString().Trim();  
                            string locationurl = baseurl.ToLower();  
                            if (!string.IsNullOrWhiteSpace(locationurl))  
                            {  
                                bool b = locationurl.StartsWith("http://") || locationurl.StartsWith("https://");  
                                if (!b)  
                                {  
                                    baseurl = new Uri(new Uri(ResponseUri), baseurl).AbsoluteUri;  
                                }  
                            }  
                            return baseurl;  
                        }  
                    }  
                }  
                catch { }  
                return string.Empty;  
            }  
        }  
    }  
    /// <summary>  
    /// 返回类型  
    /// </summary>  
    public enum ResultType  
    {  
        /// <summary>  
        /// 表示只返回字符串 只有Html有数据  
        /// </summary>  
        String,  
        /// <summary>  
        /// 表示返回字符串和字节流 ResultByte和Html都有数据返回  
        /// </summary>  
        Byte  
    }  
    /// <summary>  
    /// Post的数据格式默认为string  
    /// </summary>  
    public enum PostDataType  
    {  
        /// <summary>  
        /// 字符串类型，这时编码Encoding可不设置  
        /// </summary>  
        String,  
        /// <summary>  
        /// Byte类型，需要设置PostdataByte参数的值编码Encoding可设置为空  
        /// </summary>  
        Byte,  
        /// <summary>  
        /// 传文件，Postdata必须设置为文件的绝对路径，必须设置Encoding的值  
        /// </summary>  
        FilePath  
    }  
    /// <summary>  
    /// Cookie返回类型  
    /// </summary>  
    public enum ResultCookieType  
    {  
        /// <summary>  
        /// 只返回字符串类型的Cookie  
        /// </summary>  
        String,  
        /// <summary>  
        /// CookieCollection格式的Cookie集合同时也返回String类型的cookie  
        /// </summary>  
        CookieCollection  
    }  
    #endregion  
}