lucene.net 搜索及分页

HTWJWeb_System.HTWJSearch
{
 public partial class HTWJSearch : BaseSearch
 {

 #region 处理搜索并将信息转换为可显示结果数据源
 /**/
 /// <summary>
 /// Does the search and stores the information about the results.
 /// </summary>

 public void search()
 {

 // 索引目录
 //string indexDirectory = Server.MapPath(ConfigurationSettings.AppSettings["EnableCache"] );
 //创建一个Searcher用于搜索
 //记录查询开始的时间

 DateTime start = DateTime.Now;
 this.GetIndexDir("HTWJ", IndexDiectory);
 IndexSearcher searcher = new IndexSearcher(dir);

 //从"FullText"字段搜索
 //Console.WriteLine(this.Query);

 ChineseAnalyzer OneAnalyzer = new ChineseAnalyzer();
 BooleanClause.Occur[] flags = new BooleanClause.Occur[] {
 BooleanClause.Occur.SHOULD, BooleanClause.Occur.SHOULD };

 // Query query = QueryParser.Parse(this.Query, "FullText", new StandardAnalyzer());

 //多字段检索
 Query query = MultiFieldQueryParser.Parse(this.Query, new String[] { "Title", "FullText" }, flags, OneAnalyzer);

 //Query query = parser.Parse(this.Query);

 //创建结果记录集
 //定义字段
 this.Results.Columns.Add("File_Id", typeof(string));
 this.Results.Columns.Add("Title", typeof(string));
 this.Results.Columns.Add("FullText", typeof(string));

 Sort sort = new Sort(new SortField("Title", SortField.DOC, true));


 //Hits是搜索结果记录集,不过是Lucene自己的格式,需要格式化成标准输出
 Hits hits = searcher.Search(query, sort);
 //结果个数
 this.total = hits.Length();
 /**/
 ////创建高亮显示
 //Highlighter highlighter = new Highlighter(new SimpleHTMLFormatter("", ""), new QueryScorer(query));
 //highlighter.TextFragmenter = new SimpleFragmenter(160);
 //highlighter.MaxDocBytesToAnalyze = 256;
 // initialize startAt

 ////创建高亮显示2
 SimpleHTMLFormatter simpleHTMLFormatter = new SimpleHTMLFormatter("", "");
 Highlighter highlighter = new Highlighter(simpleHTMLFormatter, new QueryScorer(query));

 this.startAt = initStartAt();
 // how many items we should show - less than defined at the end of the results
 int resultsCount = smallerOf(total, this.maxResults + this.startAt);
 for (int i = startAt; i < resultsCount; i++)
 {
 Document doc = hits.Doc(i);
 DataRow row = this.Results.NewRow();
 row["File_Id"] = doc.Get("File_Id");

 //后期处理---链接
 row["Title"] = "<a href=\"http://www.zzu.edu.cn\" target=\"_blank\"> " + doc.Get("Title") + "</a>";

 //ChineseAnalyzer analyzer1 = new ChineseAnalyzer();
 TokenStream tokenStream = OneAnalyzer.TokenStream("FullText", new StringReader(doc.Get("FullText")));
 row["FullText"] = highlighter.GetBestFragment(tokenStream, doc.Get("FullText"));

 //用这种方法可直接创建高亮可扩展为高亮链接
 //string fullText = doc.Get("FullText");
 //row["FullText"] = this.SimpleHighLighter(fullText, this.Query, "", "", 126);

 this.Results.Rows.Add(row);
 }

 searcher.Close();
 // result information

 this.fromItem = startAt + 1;
 this.toItem = smallerOf(startAt + maxResults, total);
 //记录查询使用的时间
 this.duration = DateTime.Now - start;
 }
 #endregion

 #region 页面上面信息
 /**/
 /// <summary>
 /// 页面上面信息
 /// </summary>

 public DataTable pageinfo
 {
 get
 {
 DataTable da = new DataTable();
 da.Columns.Add("info", typeof(string));
 DataRow bar = da.NewRow();
 bar["info"] = "总共有" + this.total + "项, 用时" + this.duration + " 当前从" + this.fromItem + " 到" + this.toItem + " ";
 da.Rows.Add(bar);
 return da;
 }
 }
 #endregion

 #region 页面底航连接
 /**/
 /// <summary>
 /// 页面底航连接
 /// </summary>
 public DataTable Paging
 {
 get
 {
 int pageNumber = (startAt + maxResults - 1) / maxResults;

 DataTable dt = new DataTable();
 dt.Columns.Add("html", typeof(string));

 //增加第一页链接
 DataRow tar = dt.NewRow();
 if (startAt >= maxResults)
 tar["html"] = "<a href=\"/HTWJSearch.aspx?q=" + Server.UrlEncode(this.Query) + "&start=" + (startAt - maxResults) + "\"><IMG src=\"images/b_pre.gif\"></a>";
 else
 tar["html"] = "<IMG src=\"images/b_pre.gif\">";
 dt.Rows.Add(tar);

 int previousPagesCount = 7;

 DataRow ar = dt.NewRow();
 ar["html"] = pagingItemHtml(startAt, pageNumber + 1, false);
 dt.Rows.Add(ar);

 for (int i = pageNumber - 1; i >= 0 && i >= pageNumber - previousPagesCount; i--)
 {
 int step = i - pageNumber;
 DataRow r = dt.NewRow();
 r["html"] = pagingItemHtml(startAt + (maxResults * step), i + 1, true);

 dt.Rows.InsertAt(r, 1);
 }

 int nextPagesCount = 8;
 for (int i = pageNumber + 1; i <= pageCount && i <= pageNumber + nextPagesCount; i++)
 {
 int step = i - pageNumber;
 DataRow r = dt.NewRow();
 r["html"] = pagingItemHtml(startAt + (maxResults * step), i + 1, true);

 dt.Rows.Add(r);
 }

 //增加第一页链接
 DataRow far = dt.NewRow();
 if (pageNumber < pageCount)
 far["html"] = "<a class=\"blue1\" href=\"/HTWJSearch.aspx?q=" + Server.UrlEncode(this.Query) + "&start=" + (startAt + maxResults) + "\"><IMG src=\"images/b_nextpage.gif\"></a>";
 else
 far["html"] = "<IMG src=\"images/b_nextpage.gif\">";
 dt.Rows.Add(far);
 return dt;
 }
 }

 #region 页面连接列表

 /**//// <summary>
 /// 页面连接列表
 /// </summary>
 /// <param name="start">开始</param>
 /// <param name="number">显示数量</param>
 /// <param name="active">活动</param>
 /// <returns></returns>
 public string pagingItemHtml(int start, int number, bool active)
 {

 if (active)
 return "<VAR><a href=\"/HTWJSearch.aspx?q=" + Server.UrlEncode(this.Query) + "&start=" + start + "\">" + number + "</a></VAR>";
 else
 return "<VAR class=on>" + number + "</VAR>";
 }
 #endregion

 #endregion

 #region This should be replaced with a direct client-side get
 /// <summary>
 /// This should be replaced with a direct client-side get
 /// </summary>
 /// <param name="sender"></param>
 /// <param name="e"></param>
 protected void ButtonSearch_Click(object sender, System.EventArgs e)
 {
 this.Response.Redirect("HTWJSearch.aspx?q=" + this.TextBoxQuery.Text.Trim());
 }

 #endregion

 #region Web Form Designer generated code
 override protected void OnInit(EventArgs e)
 {
 //
 // CODEGEN: This call is required by the ASP.NET Web Form Designer.
 //
 InitializeComponent();
 base.OnInit(e);
 }

 /// <summary>
 /// Required method for Designer support - do not modify
 /// the contents of this method with the code editor.
 /// </summary>
 private void InitializeComponent()
 {

 }
 #endregion

 }

}

HTWJWeb_System
{
 public partial class BaseSearch : System.Web.UI.Page
 {

 #region 变量声明
 /**/
 /// <summary>
 /// 搜索结果数据
 /// </summary>
 public DataTable Results = new DataTable();
 /**/
 /// <summary>
 /// 开始索引
 /// </summary>
 public int startAt;
 /**/
 /// <summary>
 /// First item on page (user format).
 /// </summary>
 public int fromItem;
 /**/
 /// <summary>
 /// Last item on page (user format).
 /// </summary>
 public int toItem;
 /**/
 /// <summary>
 /// 搜索的结果总数
 /// </summary>
 public int total;
 /**/
 /// <summary>
 /// 搜索所用时间
 /// </summary>
 public TimeSpan duration;
 /**/
 /// <summary>
 /// 每页显示结果项条数
 /// </summary>
 public int maxResults = 3;
 /**/
 /// <summary>
 /// 是否启用网页缓存功能
 /// </summary>
 public bool EnableCache;
 /**/
 /// <summary>
 /// 缓存URL
 /// </summary>
 public string CacheURL;
 /**/
 /// <summary>
 /// 索引文件存放的路径
 /// </summary>
 public string IndexDiectory;
 private string m_Query;
 public Lucene.Net.Store.Directory dir;
 #endregion 变量声明

 #region 取得查询目标索引的缓存

 public void GetIndexDir(string IndexKey, string IndexDiectory)
 {
 object obj = Cache[IndexKey];
 if (obj != null)
 {
 dir = (Lucene.Net.Store.Directory)obj;
 }
 else
 {
 dir = new Lucene.Net.Store.RAMDirectory(IndexDiectory);
 //Cache.Insert(IndexKey, dir, null, DateTime.Now.AddMinutes(2), TimeSpan.Zero);
 }
 dir = new Lucene.Net.Store.RAMDirectory(IndexDiectory);
 }
 #endregion

 #region 得到定长的字符串
 /**/
 /// <summary>
 /// 得到定长的字符串
 /// </summary>
 /// <param name="p_Text">原字符串</param>
 /// <param name="p_Length">长度</param>
 /// <param name="p_ExtraText">多余部分显示字符</param>
 /// <returns></returns>
 public string GetLengthText(string p_Text, int p_Length, string p_ExtraText)
 {
 return (p_Text.Length > p_Length) ? (p_Text.Substring(0, 45) + p_ExtraText) : p_Text;
 }
 #endregion

 #region 取得两个参数中的最小值
 /**/
 /// <summary>
 /// 取得两个参数中的最小值
 /// </summary>
 /// <param name="first">参数一</param>
 /// <param name="second">参数二</param>
 /// <returns>最小值</returns>
 public int smallerOf(int first, int second)
 {
 return first < second ? first : second;
 }
 #endregion

 #region 检测开始位置
 /**/
 /// <summary>
 /// Initializes startAt value. Checks for bad values.
 /// </summary>
 /// <returns></returns>
 public int initStartAt()
 {
 try
 {
 int sa = Convert.ToInt32(this.Request.Params["start"]);
 // too small starting item, return first page
 if (sa < 0)
 return 0;
 // too big starting item, return last page
 if (sa >= total - 1)
 {
 return lastPageStartsAt;
 }
 return sa;
 }
 catch
 {
 return 0;
 }
 }
 #endregion

 #region 最后一页的第一项
 /**/
 /// <summary>
 /// First item of the last page
 /// </summary>
 public int lastPageStartsAt
 {
 get
 {
 return pageCount * maxResults;
 }
 }

 public int pageCount
 {
 get
 {
 return (total - 1) / maxResults; // floor
 }
 }
 #endregion

 #region 取得高亮显示
 /**/
 /// <summary>
 /// 取得高亮连接
 /// </summary>
 /// <param name="p_Body">处理内容</param>
 /// <param name="p_KeyWords">关键词</param>
 /// <returns></returns>
 public string SimpleHighLighter(string p_Body, string p_KeyWords, string p_Before, string p_After, int p_MaxLength)
 {
 string[] KeyWords = p_KeyWords.Trim().Split(' ');
 if (p_Body.Length > p_MaxLength)
 {
 if (p_Body.IndexOf(KeyWords[0]) > 10)
 {
 try
 {
 if ((p_Body.Length - 10) > p_MaxLength)
 p_Body = p_Body.Substring(p_Body.IndexOf(KeyWords[0]) - 10, p_MaxLength) + " lucene.net 搜索及分页

";
else
p_Body = p_Body.Substring(p_Body.IndexOf(KeyWords[0]) - 10) + " lucene.net 搜索及分页

";
                    }
                    catch
                   { }
              }
               else
                    p_Body = p_Body.Substring(0, p_MaxLength) + " lucene.net 搜索及分页

";
 }

 for (int i = 0; i < KeyWords.Length; i++)
 {
 p_Body = p_Body.Replace(KeyWords[i], p_Before + KeyWords[i] + p_After);
 }
 return p_Body;
 }
 #endregion

 #region
 private string SimpleHighLightHelper(string p_Body, string p_KeyWords)
 {
 return "";

 }
 #endregion

 #region 属性
 /**/
 /// <summary>
 /// 查询关键词
 /// </summary>
 public string Query
 {
 get
 {
 return m_Query;
 }
 set
 {
 m_Query = value;
 }
 }
 #endregion


 }
}