c# 实现网页上用户自动登陆|asp.net 模拟网站登录

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.IO;

namespace Czt.Web
{
/// <summary>
/// 实现网站登录类
/// </summary>
public class Post
{
/// <summary>
/// 网站Cookies
/// </summary>
private string _cookieHeader = string.Empty;
public string CookieHeader
{
get
{
return _cookieHeader;
}
set
{
_cookieHeader = value;
}
}
/// <summary>
/// 网站编码
/// </summary>
private string _code = string.Empty;
public string Code
{
get { return _code; }
set { _code = value; }
}
private string _pageContent = string.Empty;
public string PageContent
{
get { return _pageContent; }
set { _pageContent = value; }
}

private Dictionary<string, string> _para = new Dictionary<string, string>();
public Dictionary<string, string> Para
{
get { return _para; }
set { _para = value; }
}
/**/
/// <summary>
/// 功能描述：模拟登录页面，提交登录数据进行登录，并记录Header中的cookie
/// </summary>
/// <param name="strURL">登录数据提交的页面地址</param>
/// <param name="strArgs">用户登录数据</param>
/// <param name="strReferer">引用地址</param>
/// <param name="code">网站编码</param>
/// <returns>可以返回页面内容或不返回</returns>
public string PostData(string strURL, string strArgs, string strReferer, string code, string method)
{
return  PostData(strURL,  strArgs,  strReferer,  code,  method, string.Empty);
}
public string PostData(string strURL, string strArgs, string strReferer, string code, string method, string contentType)
{
try
{
string strResult = "";
HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(strURL);
myHttpWebRequest.AllowAutoRedirect = true;
myHttpWebRequest.KeepAlive = true;
myHttpWebRequest.Accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/msword, application/x-shockwave-flash, */*";
myHttpWebRequest.Referer = strReferer;
myHttpWebRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Maxthon; .NET CLR 2.0.50727)";

if (string.IsNullOrEmpty(contentType))
{
myHttpWebRequest.ContentType = "application/x-www-form-urlencoded";
}
else
{
myHttpWebRequest.ContentType = "contentType";
}

myHttpWebRequest.Method = method;

myHttpWebRequest.Headers.Add("Accept-Encoding", "gzip, deflate");

if (myHttpWebRequest.CookieContainer == null)
{
myHttpWebRequest.CookieContainer = new CookieContainer();
}

if (this.CookieHeader.Length > 0)
{
myHttpWebRequest.Headers.Add("cookie:" + this.CookieHeader);
myHttpWebRequest.CookieContainer.SetCookies(new Uri(strURL), this.CookieHeader);
}

byte[] postData = Encoding.GetEncoding(code).GetBytes(strArgs);
myHttpWebRequest.ContentLength = postData.Length;

System.IO.Stream PostStream = myHttpWebRequest.GetRequestStream();
PostStream.Write(postData, 0, postData.Length);
PostStream.Close();

HttpWebResponse response = null;
System.IO.StreamReader sr = null;
response = (HttpWebResponse)myHttpWebRequest.GetResponse();

if (myHttpWebRequest.CookieContainer != null)
{
this.CookieHeader = myHttpWebRequest.CookieContainer.GetCookieHeader(new Uri(strURL));
}

sr = new System.IO.StreamReader(response.GetResponseStream(), Encoding.GetEncoding(code));    //    //utf-8
strResult = sr.ReadToEnd();
sr.Close();
response.Close();
return strResult;
}
catch (Exception ex)
{
Utilities.Document.Create("C:\\error.log", strArgs, true, Encoding.UTF8);
}
return string.Empty;
}

/**/
/// <summary>
/// 功能描述：在PostLogin成功登录后记录下Headers中的cookie，然后获取此网站上其他页面的内容
/// </summary>
/// <param name="strURL">获取网站的某页面的地址</param>
/// <param name="strReferer">引用的地址</param>
/// <returns>返回页面内容</returns>
public string GetPage(string strURL, string strReferer, string code)
{
return GetPage(strURL, strReferer,code,string.Empty);
}
public string GetPage(string strURL, string strReferer,string code,string contentType)
{
string strResult = "";
HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(strURL);
myHttpWebRequest.AllowAutoRedirect = true;
myHttpWebRequest.KeepAlive = false;
myHttpWebRequest.Accept = "*/*";
myHttpWebRequest.Referer = strReferer;
myHttpWebRequest.Headers.Add("Accept-Encoding", "gzip, deflate");

myHttpWebRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Maxthon; .NET CLR 2.0.50727)";
if (string.IsNullOrEmpty(contentType))
{
myHttpWebRequest.ContentType = "application/x-www-form-urlencoded";
}
else
{
myHttpWebRequest.ContentType = contentType;
}
myHttpWebRequest.Method = "GET";

if (myHttpWebRequest.CookieContainer == null)
{
myHttpWebRequest.CookieContainer = new CookieContainer();
}

if (this.CookieHeader.Length > 0)
{
myHttpWebRequest.Headers.Add("cookie:" + this.CookieHeader);
myHttpWebRequest.CookieContainer.SetCookies(new Uri(strURL), this.CookieHeader);
}
HttpWebResponse response = null;
System.IO.StreamReader sr = null;
response = (HttpWebResponse)myHttpWebRequest.GetResponse();
Stream streamReceive;
string gzip = response.ContentEncoding;

if (string.IsNullOrEmpty(gzip) || gzip.ToLower() != "gzip")
{
streamReceive = response.GetResponseStream();
}
else
{
streamReceive = new System.IO.Compression.GZipStream(response.GetResponseStream(), System.IO.Compression.CompressionMode.Decompress);
}

sr = new System.IO.StreamReader(streamReceive, Encoding.GetEncoding(code));

if (response.ContentLength > 1)
{
strResult = sr.ReadToEnd();
}
else
{
char[] buffer=new char[256];
int count = 0;
StringBuilder sb = new StringBuilder();
while ((count = sr.Read(buffer, 0, buffer.Length)) > 0)
{
sb.Append(new string(buffer));
}
strResult = sb.ToString();
}
sr.Close();
response.Close();
return strResult;
}

}
}

from:http://www.cnblogs.com/top5/archive/2010/05/06/1728842.html