string str = "1/1/12/13/15/16/15//"; string[] strs = str.Split(new char[1] { '/' }, StringSplitOptions.RemoveEmptyEntries); List<string> new_lst_RingSize = new List<string>(); foreach (var s in strs) { if (!new_lst_RingSize.Contains(s)) { new_lst_RingSize.Add(s); } } foreach (var s in new_lst_RingSize) { Response.Write(s+"<br/>"); }