private void  main_Load(object sender, EventArgs e)
        {
            txtname.AutoCompleteMode = AutoCompleteMode.Suggest;                            
            txtname.AutoCompleteSource = AutoCompleteSource.CustomSource;                   
            AutoCompleteStringCollection DataCollection = new AutoCompleteStringCollection();
            Items(DataCollection);                                                        
            txtname.AutoCompleteCustomSource = DataCollection;                              
        }



        public void Items(AutoCompleteStringCollection Strings)
        {                                                         
            Strings.Add("azhman");                                
            Strings.Add("azhmancode");                                 
            Strings.Add("mohsen");                                  
            Strings.Add("behrooz");                                
            Strings.Add("rahmani");                               
            Strings.Add("moradi");                                   
        }