初试Lucene.net搜索及高亮分页

using System; using System.Data; using System.IO; using System.Text.RegularExpressions; using Lucene.Net.Analysis.Standard; using Lucene.Net.Documents; using Lucene.Net.QueryParsers; using Lucene.Net.Search; using Lucene.Net.Search.Highlight; using Lucene.Net.Analysis; using Lucene.Net.Index; using System.Configuration; namespace So {     public class BaseSearch : System.Web.UI.Page     {         变量声明#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 = 10;         /**//// <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         取得查询目标索引的缓存#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         得到定长的字符串#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         取得两个参数中的最小值#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         检测开始位置#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         最后一页的第一项#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         取得高亮连接#region 取得高亮连接         /**//// <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) + "";             //            else             //                p_Body = p_Body.Substring(p_Body.IndexOf(KeyWords[0]) - 10) + "";             //        }             //        catch             //        { }             //    }             //    else             //        p_Body = p_Body.Substring(0, p_MaxLength) + "";             //}             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         属性#region 属性         /**//// <summary>         /// 查询关键词         /// </summary>         public string Query         {             get             {                 return m_Query;             }             set             {                 m_Query = value;             }         }         #endregion     } } using System; using System.Data; using System.IO; using System.Text.RegularExpressions; using Lucene.Net.Analysis.Standard; using Lucene.Net.Documents; using Lucene.Net.QueryParsers; using Lucene.Net.Search; using Lucene.Net.Search.Highlight; using Lucene.Net.Analysis; using Lucene.Net.Index; using System.Configuration; namespace So.News {     public class NewsSearch : BaseSearch     {         public NewsSearch()         {             this.IndexDiectory = ConfigurationManager.AppSettings["NewsIndexPath"];         }         处理搜索并将信息转换为可显示结果数据源#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("HDC.News", IndexDiectory);             IndexSearcher searcher = new IndexSearcher(dir);             //从"body"字段搜索             //Console.WriteLine(this.Query);             Lucene.Net.Analysis.Analyzer OneAnalyzer = new StandardAnalyzer();             QueryParser parser = new QueryParser("newsContent", OneAnalyzer);             Query query = parser.Parse(this.Query);             //创建结果记录集             //定义字段             this.Results.Columns.Add("ArticleID", typeof(int));             this.Results.Columns.Add("ArticleClassID", typeof(int));             this.Results.Columns.Add("className", typeof(string));             this.Results.Columns.Add("titleImg", typeof(string));             this.Results.Columns.Add("updateTime", typeof(DateTime));             this.Results.Columns.Add("source", typeof(string));             this.Results.Columns.Add("title", typeof(string));             this.Results.Columns.Add("summary", typeof(string));             Sort sort = new Sort(new SortField("ArticleID", 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("<font color="#C60A00">", "</font>"), new QueryScorer(query));             //highlighter.TextFragmenter = new SimpleFragmenter(160);             //highlighter.MaxDocBytesToAnalyze = 256;             // initialize startAt             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["ArticleID"] = Convert.ToInt32(doc.Get("ArticleID"));                 row["ArticleClassID"] = Convert.ToInt32(doc.Get("ArticleClassID"));                 string summary = doc.Get("summary");                 row["summary"] = this.SimpleHighLighter(summary, this.Query,"<font color="#C60A00">", "</font>",226);                 row["className"] = doc.Get("className");                 row["titleImg"] = doc.Get("titleImg");                 row["updateTime"] = Convert.ToDateTime(doc.Get("updateTime"));                 row["source"] = doc.Get("source");                 row["title"] = doc.Get("title");                 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         页面底航连接#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"] = "<EM><a href="/News/?q=" + Server.UrlEncode(this.Query) + "&start=" + (startAt - maxResults) + ""><IMG src="images/b_pre.gif"></a></EM>";                 else                     tar["html"] = "<EM><IMG src="images/b_pre.gif"></EM>";                 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"] = "<EM><a class="blue1" href="/News/?q=" + Server.UrlEncode(this.Query) + "&start=" + (startAt + maxResults) + ""><IMG src="images/b_nextpage.gif"></a></EM>";                 else                     far["html"] = "<EM><IMG src="images/b_nextpage.gif"></EM>";                 dt.Rows.Add(far);                 return dt;             }         }         页面连接列表#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="/News/?q=" + Server.UrlEncode(this.Query) + "&start=" + start + "">" + number + "</a></VAR>";             else                 return "<VAR class=on>" + number + "</VAR>";         }         #endregion         #endregion     } }