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?)); //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?), "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