asp.net ajax跨二级域代理页面

/// <summary>
    /// Ajax跨二级域代理页面
    /// </summary>
    public class AjaxCrossDomainProxy : IHttpHandler
    {
        public void ProcessRequest(HttpContext context)
        {
            context.Response.Cache.SetNoStore(); //不需要客户端缓存
            context.Response.ContentType = "text/plain";
            String url = context.Request["url"];
            
            HttpWebResponse response = null;
            Stream stream = null;
            try
            {
                var request = (HttpWebRequest) WebRequest.Create(url);
                request.Headers.Add("Cookie", context.Request.Headers["Cookie"]); //将当前二级域名的cookie传送过去
                response = (HttpWebResponse) request.GetResponse();
                stream = response.GetResponseStream();
                var reader = new StreamReader(stream);
                String result = reader.ReadToEnd();
                context.Response.Write(result);
            }
            finally
            {
                if(response != null) response.Close();
                if(stream != null) stream.Dispose();
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }