C#中TextBox实现输入提示功能的方法

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using WindowsApplication7.DataSet1TableAdapters;
namespace WindowsApplication7
{
 public partial class Form1 : Form
 {
  DataSet1 ds = new DataSet1();
  CustomersTableAdapter adpter = new CustomersTableAdapter();
  public Form1()
  {
   InitializeComponent();
  }
  private void BuildAutoCompleteList()
  {
   AutoCompleteStringCollection filterVals = new AutoCompleteStringCollection();
   foreach (DataRow dr in ds.Customers)
   {
    filterVals.Add(dr["CompanyName"].ToString());
   }
   txtCompanyName.AutoCompleteCustomSource = filterVals;
  }
  private void Form1_Load(object sender, EventArgs e)
  {
   adpter.Fill(ds.Customers);
   BuildAutoCompleteList();
   }
 }
}