C# 一个特别不错的http请求类

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Net;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
using System.Text;
using System.Text.RegularExpressions;

namespace aaa
{
public class ResponseModel
{
private WebHeaderCollection header;
/// <summary>
/// 返回的头部信息集合
/// </summary>
public WebHeaderCollection Header
{
get { return header; }
set { header = value; }
}
private string html;
/// <summary>
/// 返回的文本内容
/// </summary>
public string Html
{
get { return html; }
set { html = value; }
}
private Stream stream;
/// <summary>
/// 返回的流内容
/// </summary>
public Stream Stream
{
get { return stream; }
set { stream = value; }
}

}
public class HttpHelper
{
private string accept = "application/json,text/javascrip{过滤}t,text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8";
private System.Net.CookieContainer cc = new System.Net.CookieContainer();
private string contentType = "application/x-www-form-urlencoded";

private int timeOut = 30000;
public NameValueCollection Heads = new NameValueCollection();
private bool AllowAutoRedirect = false;
bool needReset = false;
private System.Text.Encoding encoding = System.Text.Encoding.GetEncoding("utf-8");

public IWebProxy Proxy;
private string[] userAgents = new string[] { "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648; .NET CLR 3.5.21022)", "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36 SE 2.X MetaSr 1.0" };

private string userAgent
{
get
{
return this.userAgents[new Random().Next(0, this.userAgents.Length)];
}
}

/// <summary>
/// 设置下一次请求为自动重定向
/// </summary>
/// <param name="value"></param>
public void SetAllowAutoRedirectOneTime(bool value)
{
AllowAutoRedirect = value;
needReset = true;
}

/// <summary>
/// 网页访问
/// </summary>
/// <param name="url">请求地址</param>
/// <param name="isPost">是否Post</param>
/// <param name="postData">Post数据内容</param>
/// <param name="retType">返回类型0为文本,1为Stream</param>
/// <param name="cookieContainer">cookie</param>
/// <param name="refurl">Referer</param>
/// <param name="_contentType">contentType</param>
/// <param name="headers">请求头</param>
/// <returns></returns>
public ResponseModel HttpVisit(string url, bool isPost = false, string postData = null, int retType = 0, System.Net.CookieContainer cookieContainer = null, string refurl = null, string _contentType = null, NameValueCollection headers = null)
{
if (cookieContainer == null)
{
cookieContainer = this.cc;
}

if (!isPost)
{
return GetHtml(url, refurl, cookieContainer, _contentType, headers, retType);
}

ResponseModel model = new ResponseModel();

ServicePointManager.Expect100Continue = true;

ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);

HttpWebRequest request = null;
HttpWebResponse response = null;
try
{
byte[] bytes = System.Text.Encoding.Default.GetBytes(postData);
request = (HttpWebRequest)WebRequest.Create(url);
if (this.Proxy != null) request.Proxy = this.Proxy;
request.CookieContainer = cookieContainer;
request.Timeout = timeOut;
if (string.IsNullOrEmpty(_contentType))
{
request.ContentType = this.contentType;
}
else
{
request.ContentType = _contentType;
}

if (string.IsNullOrEmpty(refurl))
{
request.Referer = url;
}
else
{
request.Referer = refurl;
}

request.AllowAutoRedirect = AllowAutoRedirect;
request.Accept = this.accept;
request.UserAgent = this.userAgent;

if (headers != null)
{
request.Headers.Add(Heads);
request.Headers.Add(headers);
}
else
{
request.Headers.Add(Heads);
}

request.Method = isPost ? "POST" : "GET";
request.ContentLength = bytes.Length;

Stream requestStream = request.GetRequestStream();
requestStream.Write(bytes, 0, bytes.Length);
requestStream.Close();

if (retType == 1)
{
response = (HttpWebResponse)request.GetResponse();

model.Header = response.Headers;

Stream responseStream = response.GetResponseStream();

if (response.Cookies.Count > 0)
{
this.cc.Add(response.Cookies);
}

model.Stream = responseStream;
return model;

}

string str = string.Empty;
response = (HttpWebResponse)request.GetResponse();

model.Header = response.Headers;

string encoding = "utf-8";

if (!string.IsNullOrEmpty(response.CharacterSet))
{
encoding = response.CharacterSet.ToLower();
}
else
{
encoding = this.encoding.HeaderName;
}

if (response.ContentEncoding.ToLower().Contains("gzip"))
{

using (GZipStream stream = new GZipStream(response.GetResponseStream(), CompressionMode.Decompress))
{
using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding(encoding)))
{

str = reader.ReadToEnd();
}
}
}
else if (response.ContentEncoding.ToLower().Contains("deflate"))
{
using (DeflateStream stream = new DeflateStream(response.GetResponseStream(), CompressionMode.Decompress))
{
using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding(encoding)))
{

str = reader.ReadToEnd();
}

}
}
else
{
using (Stream stream = response.GetResponseStream())
{
using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding(encoding)))
{

str = reader.ReadToEnd();
}
}
}

request.Abort();
response.Close();
request.Abort();
if (response.Cookies.Count > 0)
{
this.cc.Add(response.Cookies);
}
model.Html = str;
return model;
}
catch (Exception ex)
{
if (request != null) request.Abort();
if (response != null)
{
response.Close();

return new ResponseModel() { Html = ex.Message, Header = response.Headers };
}
return new ResponseModel() { Html = ex.Message };
}
finally
{
if (needReset)
{
AllowAutoRedirect = false;
needReset = false;
}
}
}
/// <summary>
/// 清理string类型Cookie.剔除无用项返回结果为null时遇见错误.
/// </summary>
/// <param name="Cookies"></param>
/// <returns></returns>
public CookieCollection ClearCookie(string Cookies)
{
try
{
CookieCollection cookies = new CookieCollection();
string rStr = string.Empty;
Cookies = Cookies.Replace(";", "; ");
Regex r = new Regex("(?<=,)(?<cookie>[^ ]+=(?!deleted;)[^;]+);");
MatchCollection ms = r.Matches("," + Cookies);
foreach (Match m in ms)
{
string[] cookie = m.Groups["cookie"].Value.Split('=');

if (cookie.Length > 1)
cookies.Add(new Cookie(cookie[0], cookie[1]));

}
return cookies;
}
catch
{
return new CookieCollection();
}
}

private ResponseModel GetHtml(string url, string refurl = null, System.Net.CookieContainer cookieContainer = null, string _contentType = "", NameValueCollection headers = null, int retType = 1)
{
if (cookieContainer == null)
{
cookieContainer = this.cc;
}

ResponseModel model = new ResponseModel();

ServicePointManager.Expect100Continue = true;

ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);

HttpWebRequest request = null;
HttpWebResponse response = null;
try
{
request = (HttpWebRequest)WebRequest.Create(url);
if (this.Proxy != null) request.Proxy = this.Proxy;
request.CookieContainer = cookieContainer;
request.Timeout = timeOut;
if (string.IsNullOrEmpty(_contentType))
{
request.ContentType = this.contentType;
}
else
{
request.ContentType = _contentType;
}

if (string.IsNullOrEmpty(refurl))
{
request.Referer = url;
}
else
{
request.Referer = refurl;
}

request.AllowAutoRedirect = AllowAutoRedirect;
request.Accept = this.accept;
request.UserAgent = this.userAgent;

if (headers != null)
{
request.Headers.Add(Heads);
request.Headers.Add(headers);
}
else
{
request.Headers.Add(Heads);
}

request.Method = "GET";

if (retType == 1)
{
response = (HttpWebResponse)request.GetResponse();

model.Header = response.Headers;

Stream responseStream = response.GetResponseStream();

if (response.Cookies.Count > 0)
{
this.cc.Add(response.Cookies);
}

model.Stream = responseStream;

return model;

}

string str = string.Empty;
response = (HttpWebResponse)request.GetResponse();

model.Header = response.Headers;

string encoding = "utf-8";

if (!string.IsNullOrEmpty(response.CharacterSet))
{
encoding = response.CharacterSet.ToLower();
}
else
{
encoding = this.encoding.HeaderName;
}

if (response.ContentEncoding.ToLower().Contains("gzip"))
{

using (GZipStream stream = new GZipStream(response.GetResponseStream(), CompressionMode.Decompress))
{
using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding(encoding)))
{

str = reader.ReadToEnd();
}
}
}
else if (response.ContentEncoding.ToLower().Contains("deflate"))
{
using (DeflateStream stream = new DeflateStream(response.GetResponseStream(), CompressionMode.Decompress))
{
using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding(encoding)))
{

str = reader.ReadToEnd();
}

}
}
else
{
using (Stream stream = response.GetResponseStream())
{
using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding(encoding)))
{

str = reader.ReadToEnd();
}
}
}

if (response.Cookies.Count > 0)
{
cookieContainer.Add(response.Cookies);
}

request.Abort();
response.Close();

model.Html = str;
return model;
}
catch (Exception ex)
{
if (request != null) request.Abort();
if (response != null)
{
response.Close();

return new ResponseModel() { Html = ex.Message, Header = response.Headers };
}
return new ResponseModel() { Html = ex.Message };
}
finally
{
if (needReset)
{
AllowAutoRedirect = false;
needReset = false;
}
}
}

private bool CheckValidationResult(object sender, System.Security.Cryptography.X509Certificates.X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
{
//直接通过HTTPS的证书请求
return true;
}

public Stream GetStream(string url)
{
HttpWebRequest request = null;
HttpWebResponse response = null;
try
{
request = (HttpWebRequest)WebRequest.Create(url);
if (this.Proxy != null) request.Proxy = this.Proxy;
request.CookieContainer = this.cc;
request.ContentType = this.contentType;
//      request.ServicePoint.ConnectionLimit = this.maxTry;
request.Timeout = 0x1388;
request.Referer = url;
request.Accept = this.accept;
request.UserAgent = this.userAgent;
request.Method = "GET";
response = (HttpWebResponse)request.GetResponse();

Stream responseStream = response.GetResponseStream();
// this.currentTry--;
if (response.Cookies.Count > 0)
{
this.cc.Add(response.Cookies);
}
return responseStream;
}
catch (Exception ex)
{
//   if (this.currentTry <= this.maxTry) this.GetHtml(url, cookieContainer);
//   this.currentTry--;
if (request != null) request.Abort();
if (response != null) response.Close();
return null;
}
}

#region String与CookieContainer互转
/// <summary>
/// 将String转CookieContainer
/// </summary>
/// <param name="url"></param>
/// <param name="cookie"></param>
/// <returns></returns>
public CookieContainer StringToCookie(string url, string cookie)
{
string[] arrCookie = cookie.Split(';');
CookieContainer cookie_container = new CookieContainer();    //加载Cookie
foreach (string sCookie in arrCookie)
{
if (sCookie.IndexOf("expires") > 0)
continue;
cookie_container.SetCookies(new Uri(url), sCookie);
}
return cookie_container;
}

/// <summary>
/// 将CookieContainer转换为string类型
/// </summary>
/// <param name="cc"></param>
/// <returns></returns>
public string GetCookieString()
{
System.Collections.Generic.List<Cookie> lstCookies = new System.Collections.Generic.List<Cookie>();
Hashtable table = (Hashtable)cc.GetType().InvokeMember("m_domainTable",
System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.GetField |
System.Reflection.BindingFlags.Instance, null, cc, new object[] { });
StringBuilder sb = new StringBuilder();
foreach (object pathList in table.Values)
{
SortedList lstCookieCol = (SortedList)pathList.GetType().InvokeMember("m_list",
System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.GetField
| System.Reflection.BindingFlags.Instance, null, pathList, new object[] { });
foreach (CookieCollection colCookies in lstCookieCol.Values)
foreach (Cookie c in colCookies)
{
sb.Append(c.Name).Append("=").Append(c.Value).Append(";");
}
}
return sb.ToString();
}
#endregion

}
}