C#网页自动登录和提交POST信息的多种方法
网页自动登录和提交POST信息的核心就是分析网页的源代码（HTML），在C#中，可以用来提取网页HTML的组件比较多，常用的用WebBrowser、WebClient、HttpWebRequest这三个。
以下就分别用这三种方法来实现：
1、WebBrowser是个"迷你"浏览器，其特点是Post时不用关心Cookie、内置JS等问题
WebBrowser是VS2005新提供的组件（其实就是封装了IE接口），实现POST功能一般在webBrowser的DocumentCompleted中分析HtmlDocument 来实现，代码如下：
CodeHtmlElement ClickBtn =null;
if (e.Url.ToString().ToLower().IndexOf("http://oceanchen.cnblogs.com/") > 0) //登陆页面
{
HtmlDocument doc = webBrowser1.Document;
for (int i = 0; i < doc.All.Count ; i++)
{
if (doc.All[i].TagName.ToUpper().Equals("INPUT"))
{
switch (doc.All[i].Name)
{
case "userCtl":
doc.All[i].InnerText = "user01";
break;
case "passCt1":
doc.All[i].InnerText = "mypass";
break;
case "B1":
ClickBtn = doc.All[i]; //提交按钮
break;
}
}
}
ClickBtn.InvokeMember("Click"); //执行按扭操作
}
2、WebClient封装了HTTP的一些类，操作简单，相较于webBrowser，特点是可以自设代理，缺点是对COOKIE的控制
WebClient的运行全在后台，并且提供了异步操作的能力，这样很方便并发多个任务，然后等待结果的返回，再逐个处理。多任务异步调用的代码如下：
Codeprivate void StartLoop(int ProxyNum)
{
WebClient [] wcArray = new WebClient[ProxyNum]; //初始化
for (int idArray = 0; idArray< ProxyNum;idArray++)
{
wcArray[idArray] = new WebClient();
wcArray[idArray].OpenReadCompleted += new OpenReadCompletedEventHandler(Pic_OpenReadCompleted2);
wcArray[idArray].UploadDataCompleted += new UploadDataCompletedEventHandler(Pic_UploadDataCompleted2);
try
{
wcArray[idArray].Proxy = new WebProxy(proxy[1], port);
wcArray[idArray].OpenReadAsync(new Uri("http://oceanchen.cnblogs.com/")); //打开WEB;
proxy = null;
}
catch
{
}
}
}
private void Pic_OpenReadCompleted2(object sender, OpenReadCompletedEventArgs e)
{
if (e.Error == null)
{
string textData = new StreamReader(e.Result, Encoding.Default).ReadToEnd(); //取返回信息
..String cookie = ((WebClient)sender).ResponseHeaders["Set-Cookie"];
((WebClient)sender).Headers.Add("Content-Type", "application/x-www-form-urlencoded");
((WebClient)sender).Headers.Add("Accept-Language", "zh-cn");
((WebClient)sender).Headers.Add("Cookie", cookie);
string postData = "
"byte[] byteArray = Encoding.UTF8.GetBytes(postData); // 转化成二进制数组
((WebClient)sender).UploadDataAsync(new Uri("http://oceanchen.cnblogs.com/"), "POST", byteArray);
}
}
private void Pic_UploadDataCompleted2(object sender, UploadDataCompletedEventArgs e)
{
if (e.Error == null)
{
string returnMessage = Encoding.Default.GetString(e.Result);
}
}
3、HttpWebRequest较为低层，能实现的功能较多，Cookie操作也很简单:
Codeprivate bool PostWebRequest()
{
CookieContainer cc = new CookieContainer();
string pos tData = "user=" + strUser + "&pass=" + strPsd;
byte[] byteArray = Encoding.UTF8.GetBytes(postData); // 转化
HttpWebRequest webRequest2 = (HttpWebRequest)WebRequest.Create(new Uri(http://oceanchen.cnblogs.com/));
webRequest2.CookieContainer = cc;
webRequest2.Method = "POST";
webRequest2.ContentType = "application/x-www-form-urlencoded";
webRequest2.ContentLength = byteArray.Length;
Stream newStream = webRequest2.GetRequestStream();
// Send the data.
newStream.Write(byteArray, 0, byteArray.Length); //写入参数
newStream.Close();
HttpWebResponse response2 = (HttpWebResponse)webRequest2.GetResponse();
StreamReader sr2=new StreamReader(response2.GetResponseStream(), Encoding.Default);
string text2 = sr2.ReadToEnd();
}
HttpWebRequest 实现， 这个是从网上COPY 的！我以前用相关的代码登录到WWW.ASP.NET上，并且成功post，可惜代码不知道放什么地方了。
可以使用 Visual Sniffer（百度搜索） 来捕捉提交的数据信息：
1. 访问你需要站外提交的页面，比如 CSDN 登陆页 http://www.csdn.net/member/UserLogin.aspx
2. 填写好需要的资料，比如用户名和密码，
3. 打开 Visual Sniffer, 点“开始拦截”
4. 在访问的页面中提交。
5. 等提交成功之后，在 Visual Sniffer 中“停止拦截”
6. 在 Visual Sniffer 的左侧栏的加号中依次点开，右边是它拦截到的内容：
CodePOST http://www.csdn.net/member/UserLogin.aspx HTTP/1.0
Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-shockwave-flash, */*
Referer: http://www.csdn.net/member/UserLogin.aspx
Accept-Language: zh-cn
Content-Type: application/x-www-form-urlencoded
UA-CPU: x86
Pragma: no-cache
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; InfoPath.1)
Host: www.csdn.net
Content-Length: 355
Proxy-Connection: Keep-Alive
Cookie: ASPSESSIONIDAAAATBQC=FMEGGCKDBKHAMMCGKPFDMBFG; ASP.NET_SessionId=lusprmnom05lr445tmteaf55; userid=699879
__EVENTTARGET=&__EVENTARGUMENT=&__VIEWSTATE=dDwtMTcwMzgxNjQ2Mjs7bDxDU0ROVXNlckxvZ2luOmNiX1NhdmVTdGF0ZTtDU0ROVXNlckxvZ2luOkltYWdlX0xvZ2luOz4%2Btu1q2wmRZoAJTi9L73w1zBleylY%3D&CSDNUserLogin%3Atb_UserName=testusername&CSDNUserLogin%3Atb_Password=testpassword&CSDNUserLogin%3Atb_ExPwd=9232&from=&CSDNUserLogin%3AImage_Login.x=36&CSDNUserLogin%3AImage_Login.y=6
GET http://www.csdn.net/mycustompage.htm?aspxerrorpath=/member/UserLogin.aspx HTTP/1.0
Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-shockwave-flash, */*
Referer: http://www.csdn.net/member/UserLogin.aspx
Accept-Language: zh-cn
UA-CPU: x86
Pragma: no-cache
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; InfoPath.1)
Host: www.csdn.net
Proxy-Connection: Keep-Alive
Cookie: ASPSESSIONIDAAAATBQC=FMEGGCKDBKHAMMCGKPFDMBFG; ASP.NET_SessionId=lusprmnom05lr445tmteaf55; userid=699879
以上为拦截内容，其中提交数据的参数部分（程序中的：strArgs）如：
__EVENTTARGET=&__EVENTARGUMENT=&__VIEWSTATE=dDwtMTcwMzgxNjQ2Mjs7bDxDU
0ROVXNlckxvZ2luOmNiX1NhdmVTdGF0ZTtDU0ROVXNlckxvZ2luOkltYWdlX0xvZ2luOz4%2Btu
1q2wmRZoAJTi9L73w1zBleylY%3D&CSDNUserLogin%3Atb_UserName=testusername&CSDN
UserLogin%3Atb_Password=testpassword&CSDNUserLogin%3Atb_ExPwd=9232
Codeprotected static string cookieHeader;
private void Page_Load(object sender, System.EventArgs e)
{
string strReContent = string.Empty;
//登录
strReContent = PostLogin("http://www.mystand.com.cn/login/submit.jsp提交的页面","提交的参数：userid=hgj0000&password=06045369","引用地址：http://www.mystand.com.cn/");
//asp.net登录传递的参数需注意
//strReContent = PostLogin("http://www.mystand.com.cn/login.aspx","__VIEWSTATE=dDwtNjkzMjUyNDczO3Q8O2w8aTwzPjs%2BO2w8dDxwPHA8bDxUZXh0Oz47bDxcZTs%2BPjs%2BOzs%2BOz4%2BOz6aX2dtqkJTK%2BKbNPsjd7Op%2Fl26Iw%3D%3D&txtUserName=hxf&txtPassword=hxf0000&btnEnter=%E7%99%BB%E5%BD%95","http://www.mystand.com.cn/login.aspx");
//获取页面
strReContent = GetPage("http://www.mystand.com.cn/company/getdata.jsp?code=","引用地址：http://www.mystand.com.cn/");
//strReContent = GetPage("http://www.mystand.com.cn/Modules/index.aspx","http://www.mystand.com.cn/login.aspx");
//可以对获得的内容进行处理：strReContent
}
/**//// <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>
/// <returns>可以返回页面内容或不返回</returns>
public static string PostLogin(string strURL,string strArgs,string strReferer)
{
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)";
myHttpWebRequest.ContentType = "application/x-www-form-urlencoded";
myHttpWebRequest.Method = "POST";
CookieCollection myCookies = null;
CookieContainer myCookieContainer = new CookieContainer();
myHttpWebRequest.CookieContainer = myCookieContainer;
Stream MyRequestStrearm = myHttpWebRequest.GetRequestStream();
StreamWriter MyStreamWriter = new StreamWriter(MyRequestStrearm,Encoding.ASCII);
//把数据写入HttpWebRequest的Request流
MyStreamWriter.Write(strArgs);
//关闭打开对象
MyStreamWriter.Close();
MyRequestStrearm.Close();
HttpWebResponse response = null;
System.IO.StreamReader sr = null;
response = (HttpWebResponse)myHttpWebRequest.GetResponse();
cookieHeader = myHttpWebRequest.CookieContainer.GetCookieHeader(new Uri(strURL));
HttpContext.Current.Application.Lock();
HttpContext.Current.Application["cookieHeader"] = cookieHeader;
HttpContext.Current.Application.UnLock();
myCookies = response.Cookies;
sr = new System.IO.StreamReader(response.GetResponseStream(),Encoding.GetEncoding("gb2312")); // //utf-8
strResult = sr.ReadToEnd();
return strResult;
}
/**//// <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 static string GetPage(string strURL,string strReferer)
{
string strResult = "";
HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(strURL);
myHttpWebRequest.ContentType = "text/html";
myHttpWebRequest.Method = "GET";
myHttpWebRequest.Referer = strReferer;
myHttpWebRequest.Headers.Add("cookie:"+ cookieHeader);
HttpWebResponse response = null;
System.IO.StreamReader sr = null;
response = (HttpWebResponse)myHttpWebRequest.GetResponse();
sr = new System.IO.StreamReader(response.GetResponseStream(), Encoding.GetEncoding("gb2312")); // //utf-8
strResult = sr.ReadToEnd();
return strResult;
}
技术应用——网页自动登录（提交Post内容）的用途很多，如验证身份、程序升级、网络投票等，以下是用C#实现的方法.
未解决问题——目前最大问题无法绕过验证码——我曾经和同事讨论图片的算法，基本上很难识别，网上也有很多识别验证码的例子，但是对于简单的噪声还是可以的，可是对于复杂的就一点用都没有了！到目前为止，我没有测试成功过！如果你有测试成功过，请帖代码，我们一起研究研究。
