如何使用 WebClient 登录一个页面？

[jiangjunguo]

登录连接： http://www.metin2.org/user/login/index.php

用软件侦测 浏览器提交 username=Ncapoemchl&password=cdk890901&SubmitLoginForm=Gönder

请问WebClient 代码应该如何写？

[wuyq11]

用httpwebrequest和response类
System.Net.HttpWebRequest req=(System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(url);
req.Method= "POST ";//POST方式请求
req.ContentType= "application/x-www-form-urlencoded ";//内容类型
string para;
para=System.Web.HttpUtility.UrlEncode( "userid ") + "= "+System.Web.HttpUtility.UrlEncode("");
para+= "& ";
para+=System.Web.HttpUtility.UrlEncode( "passwd ")+ "= "+System.Web.HttpUtility.UrlEncode( "");

[jiangjunguo]

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Web;

namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
string url = "http://www.metin2.org/user/login/index.php";
HttpWebRequest req = (HttpWebRequest)HttpWebRequest.Create(url);
req.Method = "POST ";//POST方式请求
req.ContentType = "application/x-www-form-urlencoded ";//内容类型
string para;
para = HttpUtility.UrlEncode("userid ") + "= " + HttpUtility.UrlEncode("");
//这里为什么会报上下文不存在名称 HttpUtility ？
para += "& ";
para += HttpUtility.UrlEncode("passwd ") + "= " + HttpUtility.UrlEncode("");

}

}
}

[wuyq11]

添加WEB引用
using System.Web;

[jiangjunguo]

[Quote=引用 3 楼 wuyq11 的回复:]

添加WEB引用
using System.Web;
[/Quote]
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Web;
我已经加了啊，我也很奇怪为什么这里会报错。

[jiangjunguo]

找了另外一段代码，可以正常运行。 如何知道登录是成功？还失败？ 我是新手，求高人指点。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net;
using System.IO;


namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{
string Txt = "";
string UserName = "Ncapoemchl";
string UserPwd = "cdk890901";
String LoginUrl = "http://www.metin2.org/user/login/index.php";
Login(UserName, UserPwd, LoginUrl, out Txt);

//获取登录后的页面数据
textBox2.Text = Txt;

//判断该页面数据是否是登陆后的数据就可以判断是否登录成功了
//由于都是字符串操作就没有必要写了呵呵
}

public void Login(string UserName, string UserPwd, string LoginUrl, out string Txt)
{
try
{
//定义Cookie容器
CookieContainer CookieArray = new CookieContainer();

//创建Http请求
HttpWebRequest LoginHttpWebRequest = (HttpWebRequest)WebRequest.Create(LoginUrl);

//登录数据
string LoginData = "username=" + UserName + "&password=" + UserPwd + "&SubmitLoginForm=Gönder";
//数据被传输类型
LoginHttpWebRequest.ContentType = "application/x-www-form-urlencoded";
//数据长度
LoginHttpWebRequest.ContentLength = LoginData.Length;
//数据传输方法 get或post
LoginHttpWebRequest.Method = "POST";
//设置HttpWebRequest的CookieContainer为刚才建立的那个CookieArray
LoginHttpWebRequest.CookieContainer = CookieArray;
//获取登录数据流
Stream myRequestStream = LoginHttpWebRequest.GetRequestStream();
//StreamWriter
StreamWriter myStreamWriter = new StreamWriter(myRequestStream, Encoding.Default);
//把数据写入HttpWebRequest的Request流
myStreamWriter.Write(LoginData);


//关闭打开对象
myStreamWriter.Close();

myRequestStream.Close();

//新建一个HttpWebResponse
HttpWebResponse myHttpWebResponse = (HttpWebResponse)LoginHttpWebRequest.GetResponse();

//获取一个包含url的Cookie集合的CookieCollection
myHttpWebResponse.Cookies = CookieArray.GetCookies(LoginHttpWebRequest.RequestUri);

WebHeaderCollection a = myHttpWebResponse.Headers;

Stream myResponseStream = myHttpWebResponse.GetResponseStream();

StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.Default);

Txt = myStreamReader.ReadToEnd();


//把数据从HttpWebResponse的Response流中读出
myStreamReader.Close();

myResponseStream.Close();
}
catch (Exception ex)
{
throw ex;
}
}

}

}