因为response.OutputStream返回的HttpResponseStream为不能读只能写的流，故要获取其中的数据只能另想办法了，通过reflector可以发现可以用反射的方式截取其中的内容:

response内容:

private TextWriter tw_new, tw_old;

private StringBuilder _content;

private FieldInfo tw_field;

BeginRequest事件中:

_content = new StringBuilder();

tw_old = _contextApplication.Response.Output;      

tw_new = new StringWriter(_content);

var type_rp = _contextApplication.Response.GetType();

tw_field = type_rp.GetField("_writer", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

tw_field.SetValue(_contextApplication.Response, tw_new);//重新设置_write（TextWrite）的字段为tw_new，这样response.write就写写入到_content中

EndRequest事件中:

 tw_field.SetValue(_contextApplication.Response, tw_old);//还原TextWrite _write还原

 if (!string.IsNullOrEmpty(_content.ToString()))

 {

         _contextApplication.Response.Write(_content.ToString());//输入到页面_content为页面内容

}

头部:

1.获取HttpWorkerRequest类:

 HttpWorkerRequest m_workRequest = GetWorkerRequest();

 private HttpWorkerRequest GetWorkerRequest()

 {

            IServiceProvider m_provider = HttpContext.Current;

            return ((HttpWorkerRequest)m_provider.GetService(typeof(HttpWorkerRequest)));

}

2.反射获取request头部:

FieldInfo test=m_workRequest.GetType().GetField("_allRawHeaders", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

 if (test != null) 

{

        string mm = test.GetValue(m_workRequest) as string;//得到头部信息

}

当然也可以通过:

  string head = string.Empty;

for (int i = 0; i < request.Headers.Count; i++)

            {

                head += request.Headers.GetKey(i) + ":" + request.Headers[i]+"\n";

            }

3.获取页面中设置过 的resonse头部

在通过reflector观看代码过程中，无法获取到系统返回给客户端的代码，只能获取我们自己在页面中设置的头部信息,reponse头部分两种，分别对应两个字段

_customHeaders(自定义头部)_cacheHeaders缓存头部(如Expires)

 response.AddHeader("aaa", "aa");//自定义头部

            response.AddHeader("Expires", "2012-01-01");//需要缓存的头部

            //response.AddHeader("Content-Type", "text/xml");

            FieldInfo field_ResponseHeader = response.GetType().GetField("_customHeaders", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

            FieldInfo field_ResponseHeader2 = response.GetType().GetField("_cacheHeaders", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);

            if (field_ResponseHeader != null)

            {

                ArrayList collection = field_ResponseHeader.GetValue(response) as ArrayList;//获取自定义的值

                ArrayList collection2 = field_ResponseHeader2.GetValue(response) as ArrayList;//获取缓存头部添加的值

            }

IIS中可以设置返回给浏览器的头部信息，尽量去掉无用的头部信息以减少流量