lucenc.net 全文检索 创建索引、 查询、分页

 #region 创建、跟新词库
        /// <summary>
        /// 创建、跟新词库
        /// </summary>
        private void CreateIndexData()
        {
            //索引库文件夹
            FSDirectory dir = FSDirectory.Open(new DirectoryInfo(path), new NativeFSLockFactory());
            //是否存在索引库
            bool has = IndexReader.IndexExists(dir);
            if (has)
            {
                //解锁被锁定的索引库
                if (IndexWriter.IsLocked(dir))
                {
                    IndexWriter.Unlock(dir);
                }
            }
            //索引库写对象
            IndexWriter iw = new IndexWriter(dir, new PanGuAnalyzer(), !has, IndexWriter.MaxFieldLength.UNLIMITED);
            List<LuceneModel> list = LuceneBll.Instance.Get();
            foreach (var o in list)
            {
                Document d = new Document();
                //Field.Store.YES:                         存储字段值（未分词前的字段值） 
                //Field.Store.NO:                          不存储,存储与索引没有关系 
                //Field.Store.COMPRESS:                    压缩存储,用于长文本或二进制，但性能受损 

                //Field.Index ANALYZED;                    分词建索引
                //Field.Index ANALYZED_NO_NORMS;           分词压缩建索引
                //Field.Index NO;
                //Field.Index NOT_ANALYZED;                不分词建索引
                //Field.Index NOT_ANALYZED_NO_NORMS;       不分词压缩建索引

                //Field.TermVector NO;                      
                //Field.TermVector WITH_OFFSETS;           存储偏移量
                //Field.TermVector WITH_POSITIONS;         存储位置
                //Field.TermVector WITH_POSITIONS_OFFSETS; 存储位置和偏移量
                //Field.TermVector YES;                    为每个文档（Document）存储该字段的TermVector

                d.Add(new Field("Id", o.Id.ToString(), Field.Store.YES, Field.Index.NOT_ANALYZED));
                d.Add(new Field("Title", o.Title, Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS));
                d.Add(new Field("Message", o.Message, Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS));
                iw.AddDocument(d);
            }
            iw.Optimize();
            //释放文件
            iw.Close();
            dir.Close();
        }
        #endregion

#region 查询
        /// <summary>
        /// 查询
        /// </summary>
        /// <param name="str">要查询的关键字</param>
        /// <param name="index">页索引(从1开始)</param>
        /// <param name="count">每页显示数据条数</param>
        /// <returns></returns>
        private List<LuceneModel> Search(string str, int index = 1, int count = 3)
        {
            List<LuceneModel> list = null;
            //索引库文件夹
            FSDirectory dir = FSDirectory.Open(new DirectoryInfo(path), new NativeFSLockFactory());
            //是否存在索引库
            bool has = IndexReader.IndexExists(dir);
            //不存在则创建
            if (!has)
            {
                //创建索引库
                CreateIndexData();
            }
            //索引库读对象
            IndexReader ir = IndexReader.Open(dir, true);
            //索引库查询对象
            IndexSearcher searcher = new IndexSearcher(ir);
            //搜索条件
            PhraseQuery query = new PhraseQuery();
            //分词
            {
                Segment segment = new Segment();
                ICollection<WordInfo> words = segment.DoSegment(str);
                foreach (var o in words)
                {
                    query.Add(new Term("Message", o.ToString()));
                }
            }
            //指定关键词相隔最大距离
            query.SetSlop(100);
            //盛放查询结果的容器
            TopScoreDocCollector collector = TopScoreDocCollector.create(index * count, false);
            //根据query查询条件进行查询
            searcher.Search(query, null, collector);
            ScoreDoc[] docs = collector.TopDocs(count * (index - 1), count * (index - 1) + count).scoreDocs;
            if (docs.Length > 0)
            {
                list = new List<LuceneModel>();
                foreach (var o in docs)
                {
                    Document document = searcher.Doc(o.doc);
                    LuceneModel m = new LuceneModel();
                    m.Id = Convert.ToInt32(document.Get("Id"));
                    m.Title = document.Get("Title");
                    m.Message = document.Get("Message");
                    list.Add(m);
                }
            }
            //释放文件
            ir.Close();
            searcher.Close();
            dir.Close();
            return list;
        }
        #endregion

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