将WebBrowser的cookie信息传给HttpWebRequest

            //获取浏览器的cookies
            string Webcookies = webBrowser.Document.Cookie;
            //通过HTTP请求加载测试
            HttpHelper http = new HttpHelper();
            HttpItem item = new HttpItem()
            {
                URL = this.contacturl,
                Method = "get",
                Encoding = Encoding.UTF8,
                Cookie = Webcookies,
                Accept= "application/json, text/javascript, */*; q=0.01",
                ContentType = "text/plain",
                UserAgent =
                   "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36",
            };
            item.Header.Add("Accept-Language", "zh-CN,zh;q=0.8");
            item.Header.Add("X-Requested-With", "XMLHttpRequest");
            item.Header.Add("Accept-Encoding", "gzip, deflate, sdch, br");
            //得到HTML代码
            HttpResult result = http.GetHtml(item);
            string html = result.Html;