下面这段代码是我转别人的,我就是看这段学的.
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string indata="aa=zhuye";
string outdata="";
CookieContainer myCookieContainer=new CookieContainer();
//新建一个CookieContainer来存放Cookie集合
HttpWebRequest myHttpWebRequest=(HttpWebRequest)WebRequest.Create(url);
//新建一个HttpWebRequest
myHttpWebRequest.ContentType="application/x-www-form-urlencoded";
myHttpWebRequest.ContentLength=indata.Length;
myHttpWebRequest.Method="POST";
myHttpWebRequest.CookieContainer=myCookieContainer;
//设置HttpWebRequest的CookieContainer为刚才建立的那个myCookieContainer
Stream myRequestStream=myHttpWebRequest.GetRequestStream();
StreamWriter myStreamWriter=new StreamWriter(myRequestStream,Encoding.GetEncoding("gb2312"));
myStreamWriter.Write(indata);
//把数据写入HttpWebRequest的Request流
myStreamWriter.Close();
myRequestStream.Close();
//关闭打开对象
HttpWebResponse myHttpWebResponse=(HttpWebResponse)myHttpWebRequest.GetResponse();
//新建一个HttpWebResponse
myHttpWebResponse.Cookies=myCookieContainer.GetCookies(myHttpWebRequest.RequestUri);
//获取一个包含url的Cookie集合的CookieCollection
Stream myResponseStream=myHttpWebResponse.GetResponseStream();
StreamReader myStreamReader=new StreamReader(myResponseStream,Encoding.GetEncoding("gb2312"));
outdata=myStreamReader.ReadToEnd();
//把数据从HttpWebResponse的Response流中读出
myStreamReader.Close();
myResponseStream.Close();
Console.WriteLine(outdata);
//显示"登录"
//拿到了Cookie，再进行请求就能直接读取到登录后的内容了
myHttpWebRequest=(HttpWebRequest)WebRequest.Create(url);
myHttpWebRequest.CookieContainer=myCookieContainer;//*
//刚才那个CookieContainer已经存有了Cookie,把它附加到HttpWebRequest中则能直接通过验证
myHttpWebResponse=(HttpWebResponse)myHttpWebRequest.GetResponse();
myHttpWebResponse.Cookies=myCookieContainer.GetCookies(myHttpWebRequest.RequestUri);
myResponseStream=myHttpWebResponse.GetResponseStream();
myStreamReader=new StreamReader(myResponseStream,Encoding.GetEncoding("gb2312"));
outdata=myStreamReader.ReadToEnd();
myStreamReader.Close();
myResponseStream.Close();
Console.WriteLine(outdata);
//再次显示"登录"
//如果把*行注释调，就显示"没有登录"
}
注释写得很明确了，不多罗嗦了。
补充：如果是以get方式登录的话，直接修改url就可以了，indate可以不写任何东西。（不要去修改myHttpWebRequest.Method为GET），比如把asp文件修改为if request.querystring("aa")="zhuye" then session("ok")="ok"，只要修改url为string url="http://localhost/csdn2/1.asp?aa=zhuye";即可。