当我们在搜索框输入关键字的时候，Google会自动列出相关关键字提示。用asp.net Ajax AutoCompleteExtender控件实现
运行环境行vs 2008 .net 3.5sp1 需单独安装ajax控件工具集
Code <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %><%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head runat="server"> <title>无标题页</title></head><body> <form id="form1" runat="server"> <div><asp:ScriptManager ID="ScriptManager1" runat="server" /> <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> <cc1:AutoCompleteExtender ID="AutoCompleteExtender1" runat="server" TargetControlID="TextBox1" ServiceMethod="GetCompletionList" CompletionSetCount="10" MinimumPrefixLength="2" EnableCaching="true" UseContextKey="True"> </cc1:AutoCompleteExtender> </div> </form></body></html> Code using System;using System.Collections;using System.Configuration;using System.Data;using System.Linq;using System.Web;using System.Web.Security;using System.Web.UI;using System.Web.UI.HtmlControls;using System.Web.UI.WebControls;using System.Web.UI.WebControls.WebParts;using System.Xml.Linq;using System.Collections.Generic;using System.Data.SqlClient;public partial class _Default : System.Web.UI.Page { [System.Web.Services.WebMethodAttribute(), System.Web.Script.Services.ScriptMethodAttribute()] public static string[] GetCompletionList(string prefixText, int count, string contextKey) { SqlConnection conn; SqlCommand cmd; string cmdString = "Select CompanyName from Customers WHERE CompanyName LIKE '" + prefixText + "%'"; conn = new SqlConnection(@"Data Source=.;DataBase=Northwind;UID=sa;PWD=sa;"); // Put this string on one line in your code cmd = new SqlCommand(cmdString, conn); conn.Open(); SqlDataReader myReader; List<string> returnData = new List<string>(); myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection); while (myReader.Read()) { returnData.Add(myReader["CompanyName"].ToString()); } return returnData.ToArray(); } }