private string LoadAdvertisements(string paramsToAdd, int pageNumber) { string url = $@"{Urls.Ads}?{paramsToAdd}"; HttpWebRequest request = crawler.CreateWebRequest(url); request.KeepAlive = true; request.Headers.Add("Upgrade-Insecure-Requests", "1"); request.UserAgent = UserAgent; request.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3"; if (!string.IsNullOrEmpty(referer)) { request.Referer = pageNumber == 1 ? Urls.SearchPage : referer; } request.Headers.Add("Accept-Language", "en-GB,en;q=0.9"); request.Method = "GET"; try { HttpWebResponse response = crawler.GetResponse(request); WriteLine(url + " " + response.StatusCode); referer = response?.GetPageUrl(); return(response.ToStringValue()); } catch { return(string.Empty); } }