Ajax智能匹配检索（含图含完整代码）

        "ScriptManager1" runat="server" />
        "AutoCompleteExtender1" runat="server" TargetCOntrolID="TextBox1"
                ServicePath="KeyFind.asmx" CompletiOnSetCount="10" MinimumPrefixLength="1" ServiceMethod="GetCompleteDepart">
        
        "TextBox1" runat="server" 352px" 27px">

using System;
using System.Web;
using System.Collections;
using System.Web.Services;
using System.Web.Services.Protocols;
//引入空间
using System.Data;
using System.Data.OleDb;
using System.Configuration;
/// 

/// KeyFind 的摘要说明
/// 
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
//添加服务脚本（必须添，否则程序不能正常运行）
[System.Web.Script.Services.ScriptService]
public class KeyFind : System.Web.Services.WebService
{

    public KeyFind()
    {
        //如果使用设计的组件，请取消注释以下行 
        //InitializeComponent(); 
    }
    //定义数组保存获取的内容
    private string[] autoCompleteWordList = null;

    //两个参数“prefixText”表示用户输入的前缀，count表示返回的个数
    [WebMethod]
    public String[] GetCompleteDepart(string prefixText, int count)
    {
        ///检测参数是否为空
        if (string.IsNullOrEmpty(prefixText) == true || count <= 0) return null;
        // 如果数组为空
        if (autoCompleteWordList == null)
        {
            //读取数据库的内容
            OleDbConnection cOnn= new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + Server.MapPath("Ex18_02.mdb"));
            conn.Open();
            OleDbDataAdapter da = new OleDbDataAdapter("select keyName from keyInfo  where keyName like'" + prefixText + "%' order by keyName", conn);
            DataSet ds = new DataSet();
            da.Fill(ds);
            //读取内容文件的数据到临时数组
            string[] temp = new string[ds.Tables[0].Rows.Count];
            int i = 0;
            foreach (DataRow dr in ds.Tables[0].Rows)
            {
                temp[i] = dr["keyName"].ToString();
                i++;
            }
            Array.Sort(temp, new CaseInsensitiveComparer());
            //将临时数组的内容赋给返回数组
            autoCompleteWordList = temp;
            if (conn.State == ConnectionState.Open)
                conn.Close();
        }
        //定位二叉树搜索的起点
        int index = Array.BinarySearch(autoCompleteWordList, prefixText, new CaseInsensitiveComparer());
        if (index <0)
        {   //修正起点
            index = ~index;
        }
        //搜索符合条件的数据
        int matchCount = 0;
        for (matchCount = 0; matchCount )
        {   ///查看开头字符串相同的项
            if (autoCompleteWordList[index + matchCount].StartsWith(prefixText, StringComparison.CurrentCultureIgnoreCase) == false)
            {
                break;
            }
        }
        //处理搜索结果
        string[] matchResultList = new string[matchCount];
        if (matchCount > 0)
        {   //复制搜索结果
            Array.Copy(autoCompleteWordList, index, matchResultList, 0, matchCount);
        }
        return matchResultList;
    }
}