最近我一直在研究 Lucene.net ,發現Lucene.net對數據庫方面建索引的文章在網上很少見,其實它是可以對數據庫進行索引的,我閒着沒事,寫了個測試程序,竟然成功了, 可以實現對數據另類查詢的一種方式(通過建索引查詢),發表出來,和大家共享.
其實 Lucene.net 對數據庫建索引很簡單,只要把數據表裏面的記錄讀出來,然後對每個字段索引就行了.本文中數據庫的內容是某個博客表－userblog表。
1.表結構:
字段名稱 字段類型 字段含義
id Varchar(11) 編號
title Varchar(50) 標題
content Text 內容
2.程序流程
1) 打開數據庫;
2) 建立索引;
3) 根據索引進行全文搜索.
4.附源碼:
aspx文件:
如轉載請註明出處,謝謝!!
wangkun by 2007-5-1
<%@ Page language="c#" Codebehind="WebForm1.aspx.cs" AutoEventWireup="false" Inherits="WebApplication4.WebForm1" %><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" ><HTML> <HEAD> <title>使用Lucene.net建立簡單的數據庫搜索程序</title> <meta content="Microsoft Visual Studio .NET 7.1" name="GENERATOR"> <meta content="C#" name="CODE_LANGUAGE"> <meta content="JavaScript" name="vs_defaultClientScript"> <meta content="http://schemas.microsoft.com/intellisense/ie5" name="vs_targetSchema"> </HEAD> <body MS_POSITIONING="GridLayout"> <form id="Form1" method="post" runat="server"> <table width="100%" border="0"> <tr> <td> <asp:textbox id="tj" runat="server"></asp:textbox><asp:button id="Search" runat="server" Text="搜索"></asp:button></td> </tr> </table> <table width="100%" border="0"> <tr> <td><asp:datagrid id="SearGrid" runat="server" AutoGenerateColumns="False"> <Columns> <asp:TemplateColumn> <HeaderTemplate> 搜索結果: </HeaderTemplate> <ItemTemplate> <table width="100%" border="0"> <tr> <td>id:<%# DataBinder.Eval(Container.DataItem,"id") %> </td> </tr> <tr> <td>標題: <%# DataBinder.Eval(Container.DataItem,"title") %> </td> </tr> <tr> <td>內容: <%# DataBinder.Eval(Container.DataItem,"content") %> </td> </tr> <tr> <td> </td> </tr> </table> </ItemTemplate> </asp:TemplateColumn> </Columns> </asp:datagrid></td> </tr> </table> </form> </body></HTML>cs代碼
using System;using System.Collections;using System.ComponentModel;using System.Data;using System.Data.SqlClient;using System.Drawing;using System.Web;using System.Web.SessionState;using System.Web.UI;using System.Web.UI.WebControls;using System.Web.UI.HtmlControls;using Lucene.Net;using Lucene.Net.Index;using Lucene.Net.Documents;using Lucene.Net.QueryParsers;using Lucene.Net.Search;using Lucene.Net.Analysis.Standard;using Lucene.Net.Analysis.Cn;namespace WebApplication4
{
/// <summary>
/// WebForm1 的摘要說明。
/// </summary> public class WebForm1 : System.Web.UI.Page { protected System.Web.UI.WebControls.TextBox tj; protected System.Web.UI.WebControls.Button Search; protected System.Web.UI.WebControls.DataGrid SearGrid; public string connstr="server=.;database=TopWin2;uid=sa;pwd="; private void Page_Load(object sender, System.EventArgs e) { // 在此處放置用戶代碼以初始化頁面 if (!Page.IsPostBack) { //打開數據庫表 SqlDataReader myred=OpenTable(); //建立索引 IndexWriter writer=CreateIndex(myred); } } public SqlDataReader OpenTable() { SqlConnection mycon=new SqlConnection(connstr); mycon.Open(); SqlCommand mycom=new SqlCommand("select id,title,content from userblog order by id",mycon); return mycom.ExecuteReader(); } public IndexWriter CreateIndex(SqlDataReader myred) { IndexWriter writer = new IndexWriter("c:/index/", new ChineseAnalyzer(), true); try { //建立索引字段 while(myred.Read()) { Document doc=new Document(); doc.Add(Field.Keyword("id",myred["id"].ToString())); doc.Add(Field.Text("title",myred["title"].ToString())); doc.Add(Field.Text("content",myred["content"].ToString())); writer.AddDocument(doc); } writer.Optimize(); writer.Close(); } catch(Exception e) { Response.Write(e); } return writer; } public Hits seacher(String queryString) { Hits hits=null; try { IndexSearcher mysea=new IndexSearcher("c:/index/"); Query query=QueryParser.Parse(queryString,"content",new ChineseAnalyzer()); hits=mysea.Search(query); } catch(Exception e) { Response.Write(e); } return hits; }
Web 窗體設計器生成的代碼 private void Search_Click(object sender, System.EventArgs e) { DataRow myrow; DataTable mytab=new DataTable(); mytab.Columns.Add("id"); mytab.Columns.Add("title"); mytab.Columns.Add("content"); mytab.Clear(); Hits myhit=seacher(this.tj.Text.Trim()); if (myhit!=null) { for(int i=0;i<myhit.Length();i++) { Document doc=myhit.Doc(i); myrow=mytab.NewRow(); myrow[0]=doc.Get("id").ToString(); myrow[1]=doc.Get("title").ToString(); myrow[2]=doc.Get("content").ToString(); mytab.Rows.Add(myrow); myrow.AcceptChanges(); } this.SearGrid.DataSource=mytab; this.SearGrid.DataBind(); } else { // } } }
}