初学抓包之登录

最近一直忙于学习抓包  一直没有更新博客   要抓取别人的得数据  首先 要进入他们的网站  所以我就用客户端模拟浏览器登录   那么就要用到htmlagliitypack这个库了  可以在vs里面直接安装  you最新的版本

            private CNNWebClient webClient；
            HtmlDocument html = new HtmlDocument();
            string loginHtml = webClient.DownloadString("xxxxxx");//登录的网址
            html.LoadHtml(loginHtml);
            //判断登录是否有效
            HtmlNode success = html.DocumentNode.SelectSingleNode("//*[@id="wrapper"]/div[1]/div[2]/div/div[2]/a[2]");
            //若登录还有效直接返回登录成功
            if (success != null)
                return new HttpMessage() { Reslut = success.InnerText };
            //*[@id="fm1"]/div[4]/input[1]
            string lt = html.DocumentNode.SelectSingleNode("//*[@id="fm1"]/div[4]/input[1]").Attributes["value"].Value;//htmlagliitypack的属性获取网页上的值
            string execution = html.DocumentNode.SelectSingleNode("//*[@id="fm1"]/div[4]/input[2]").Attributes["value"].Value;
            string postData = string.Format("username={2}&password={3}&remember=1&lt={0}&execution={1}&_eventId=submit"
                             , lt, execution, UserName, HttpUtility.UrlDecode(PassWord));//格式化字符串  用于提交
            
             webClient.Headers.Add("Content-Type", "application/x-www-form-urlencoded");//post提交必须加这个 
             webClient.Headers.Add("User-Agent", "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)");

            string postHtml = webClient.UploadString("xxxxxxxxxx", postData);//登录
            webClient.Headers.Add("Content-Type", "text/html;charset=UTF-8");
            HtmlDocument index = new HtmlDocument();
            string indexRes = webClient.DownloadString("http://eip.chinatowercom.cn/");
            index.LoadHtml(indexRes);//加载首页判断是否登录成功
            success = index.DocumentNode.SelectSingleNode("//*[@id="wrapper"]/div[1]/div[2]/div/div[2]/a[2]");

            if (success == null)
                return new HttpMessage() { Reslut = postHtml, State = false };
            else
            {
                //   _addMeaage(string.Format("{0}--登录成功--", success.InnerText));
                return new HttpMessage() { Reslut = success.InnerText };
            }

　　这是登录的方法  还有客户端登录  保持cookie或者session  这个很重要  

 public class CNNWebClient : WebClient
    {
        private Calculagraph _timer;
        private int _timeOut = 10;
        

        /**/
        /// <summary>
        /// 返回带有 Cookie 的 HttpWebRequest。
        /// </summary>
        /// <param name="address"></param>
        /// <returns></returns>
        protected override WebRequest GetWebRequest(Uri address)
        {
            WebRequest request = base.GetWebRequest(address);
            if (request is HttpWebRequest)
            {
                HttpWebRequest httpRequest = request as HttpWebRequest;
                httpRequest.CookieContainer = cookieContainer;
                httpRequest.Timeout = 1000 * Timeout;
                httpRequest.ReadWriteTimeout = 1000 * Timeout;
            }
            return request;
        }

        /// <summary>
        /// 过期时间
        /// </summary>
        public int Timeout
        {
            get
            {
                return _timeOut;
            }
            set
            {
                if (value <= 0)
                    _timeOut = 10;
                _timeOut = value;
            }
        }
}gan

　　这就是基本的登录方法了  希望能给大家一点灵感  对于程序员来说  有时候  一点灵感  足以解决困扰几天的问题