C#网页自动登录和提交

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。        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：

            HtmlElement ClickBtn =null;                        if (e.Url.ToString().ToLower().IndexOf("xxx.htm") > 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：

    private 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://xxxx.com.cn/tp.asp?Id=129")); //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://xxxxxxy.com.cn/tp.asp?Id=129"), "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

        private 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://www.xxxx.com/chk.asp"));                                 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同样提供了异步操作，有兴趣的朋友自己查MSDN，实现起来也不难。

 

转自：http://www.cnblogs.com/yuanbao/archive/2007/08/31/865108.html