public void RefreshList() { ABCServices services = new ABCServices(); List <Clients> clients = services.FindAllClients(); // WHY IS FOLLOWING LINES????????? List <int> myintlist = new List <int>(); myintlist.Add(11); myintlist.Add(1001); myintlist.Add(10021); myintlist.Add(10013); myintlist.Add(10014); myintlist.Where(o => o > 999).Count(); ListClient.Items.Clear(); foreach (var item in clients) { ListClient.Items.Add(item.ClientID + " - " + item.ClientName + " - " + item.ClientPhone); } }