本文實例講述了C#使用WebClient登錄網站并抓取登錄后的網頁信息實現方法。分享給大家供大家參考，具體如下：
C#登錄網站實際上就是模擬瀏覽器提交表單，然后記錄瀏覽器響應返回的會話Cookie值，再次發送請求時帶著這個會話cookie值去請求就可以實現模擬登錄的效果了。
如下類CookieAwareWebClient實現在發送請求時都帶著cookie。
|
1
2
3
4
5
6
7
8
9
10
11
12
13
|
public class CookieAwareWebClient : WebClient{ private CookieContainer cookie = new CookieContainer(); protected override WebRequest GetWebRequest(Uri address) { WebRequest request = base.GetWebRequest(address); if (request is HttpWebRequest) { (request as HttpWebRequest).CookieContainer = cookie; } return request; }} |
如下是模擬表單提交登錄的使用示例：
|
1
2
3
4
5
6
7
8
|
var client = new CookieAwareWebClient();client.BaseAddress = @"https://hovertree.net/any/base/url/";var loginData = new NameValueCollection();loginData.Add("login", "YourLogin");loginData.Add("password", "YourPassword");client.UploadValues("login.php", "POST", loginData);//Now you are logged in and can request pagesstring htmlSource = client.DownloadString("index.php"); |
希望本文所述對大家C#程序設計有所幫助。
