How Can I Get The Users Of Some Specific Id

string ip1 = "10.236.105.108";
           string ip2 = "10.236.105.208";
           string st = Convert.ToString(ip1.Substring(ip1.LastIndexOf('.') + 1));
           string lt = Convert.ToString(ip2.Substring(ip2.LastIndexOf('.') + 1));

           for (int i = Convert.ToInt32(st); i <= Convert.ToInt32(lt); i++)
           {
               string addr = ip1.Substring(0, ip1.LastIndexOf('.')) + '.' + i;
               IPHostEntry entry = Dns.GetHostEntry(addr);
           }