C#通过httpwebrequest保持会话ID

Question

当使用C#.Net(像爬虫)浏览网站的页面时,我需要保留相同的会话ID.我发现了一些方法,http嗅探器非常方便,比较我的IE浏览器发送的内容(HTTP请求)和从Web服务器接收(HTTP响应),因为重要信息在标题中(未显示)通过浏览器).请不要在服务器到浏览器之间公开的会话ID和服务器代码私有的服务器会话变量(如php)之间混淆.

WebHeaderCollection headerCollection = new WebHeaderCollection();
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
  /* save headers */
  for (int i = 0; i < response.Headers.Count; i++)
  {
     headerCollection.Add(response.Headers.AllKeys[i], response.Headers.Get(i));
  }
  /* save cookies */
  cookieContainer = new CookieContainer();
  foreach (Cookie cookie in response.Cookies)
  {
    cookieContainer.Add(cookie);
  }
}

发出其他GET或POST请求:

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
...
/* restore PHPSESSID */
for (int i = 0; i < headerCollection.Count; i++)
{
 string key = headerCollection.GetKey(i);
 if (key == "Set-Cookie")
 {
  key = "Cookie";
 }
 else
 {
  continue;
 }
 string value = headerCollection.Get(i);
 request.Headers.Add(key, value);
}
/* restore cookies */
request.CookieContainer = cookieContainer;
/* complete request */
Stream writeStream = request.GetRequestStream()

我的要求是提供更好的代码或其他想法,以保持更好的爬虫会话.

Answer 1

如果您创建一个cookie容器并将其分配给您的第一个和第二个请求,则无需执行从响应中复制Cookie的所有操作.

当响应设置cookie时,附加请求的cookie容器将接收并存储这些cookie.因此,在一系列请求之间维护相同的会话上下文只需维护一个cookie容器实例并将其与所有请求一起使用.

你的代码变成: -

cookieContainer = new CookieContainer();
request.CookieContainer = cookieContainer;
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
  // Do stuff with response
}

然后:-

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
...

request.CookieContainer = cookieContainer;
Stream writeStream = request.GetRequestStream()