static void Main(string[] args) { c = new ContactClient(); c.BeginGetFirst10(new AsyncCallback(GetFirst10Completed), null); c.BeginGetByContactId(1, new AsyncCallback(GetByContactIdCompleted), null); c.BeginGetByContactId(10, new AsyncCallback(GetByContactIdCompleted), null); c.BeginGetByContactId(100, new AsyncCallback(GetByContactIdCompleted), null); c.BeginGetByContactId(1000, new AsyncCallback(GetByContactIdCompleted), null); c.BeginGetByContactId(10000, new AsyncCallback(GetByContactIdCompleted), null); Console.ReadKey(); }