Попробуйте украсить заголовки вашего запроса следующим образом:
Uri url = new Uri("https://1xbetm.mobi/LineFeed/Get1x2_VZip?sports=1&count=500&lng=tr&tf=1500000&tz=3&mode=4&country=190&getEmpty=true");
System.Net.WebClient client = new System.Net.WebClient();
client.Headers.Add ("user-agent", "Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko");
string jsonOneXBetData = client.DownloadString(url);
Редактировать 1:
Для другого URL, похоже, нужны еще 2 параметра заголовка:
Uri url = new Uri("https://www.86tempobet.com?reloadlive=240671122&no_write_sess=1");
System.Net.WebClient client = new System.Net.WebClient();
client.Headers.Add ("user-agent", "Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko");
client.Headers.Add("method","POST");
client.Headers.Add("cookie","{cookie}");
string jsonOneXBetData = client.DownloadString(url);
Редактировать 2:
Вот полный запрос на доступ к ответу как json:)
Uri url = new Uri("https://www.86tempobet.com?reloadlive=240671122&no_write_sess=1");
System.Net.WebClient client = new System.Net.WebClient();
client.Headers.Add ("user-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36");
client.Headers.Add("method","POST");
client.Headers.Add("cookie","visid_incap_1875943=C4HkVjo8RCCFldh593iChSbq6VsAAAAAQUIPAAAAAABzSYMXxV4TSKKZijRL24QX; incap_ses_277_1875943=ZnjKE7twmRYrT7s2YxvYAybq6VsAAAAAFdaEfL/KiNMUMywbnQeCNA==; GAMBLINGSESS=jfr3uadgl1ogv55c06ee6mvvs3fiv86p; nlbi_1875943=4NdhZ5rR80YChdm11QdqAQAAAAA3PlRp/yXvrsgK9rbvAEPs; _ga=GA1.2.449421393.1542056499; _gid=GA1.2.2110672116.1542056499; docscrollltop=0; LPVID=FkMTc4MDEwMzY3NDllNjU5; LPSID-34568906=eQOy1bjvTWS3lx1mTF5b3w");
client.Headers.Add("x-requested-with","XMLHttpRequest");
client.Headers.Add("betslip-hash","578c9b9896d955c14a698bf17937400a");
client.Headers.Add("content-type","application/x-www-form-urlencoded; charset=UTF-8");
client.Headers.Add("ajax-json","true");
string jsonOneXBetData = client.DownloadString(url);