使用Lucene.NET实现数据检索功能
1、索引的管理
//指定索引库文件存放文件位置 FSDirectory directory = FSDirectory.Open(new DirectoryInfo(this.IndexDataDir), new NativeFSLockFactory()); //判断索引文件目录是否存在 bool isExist = IndexReader.IndexExists(directory); if (isExist) { if (IndexWriter.IsLocked(directory)) { IndexWriter.Unlock(directory); } } //盘古分词器 PanGuAnalyzer analyzer = new PanGuAnalyzer(); //索引写入类 IndexWriter writer = new IndexWriter(directory, analyzer, !isExist, IndexWriter.MaxFieldLength.UNLIMITED); //循环队列执行操作 while (IndexDataQueue.Count > 0) { Document document = new Document(); //这是我为索引数据自定义的模型类,主要内容是文件的路径、名称、内容和索引管理的操作类型(新增、更新、删除) BaseDataMode mode = IndexDataQueue.Dequeue(); switch (mode.Type) { case OperationType.Insert: { foreach (KeyValuePair<string, string> kv in mode.Content) { //这里kv.Key是设置索引内字段的名称,kv.Value是这个字段内存储的内容。 document.Add(new Field(kv.Key, kv.Value, Field.Store.YES, Field.Index.ANALYZED,Field.TermVector.WITH_POSITIONS_OFFSETS)); } writer.AddDocument(document); }; break; case OperationType.Update: { //设置删除条件 MultiFieldQueryParser parser = new MultiFieldQueryParser(Lucene.Net.Util.Version.LUCENE_29, new string[] { "id" }, analyzer); Query query = parser.Parse(mode.Content["id"]); writer.DeleteDocuments(query); foreach (KeyValuePair<string, string> kv in mode.Content) { document.Add(new Field(kv.Key, kv.Value, Field.Store.YES, Field.Index.ANALYZED,Field.TermVector.WITH_POSITIONS_OFFSETS)); } writer.AddDocument(document); }; break; case OperationType.Delete: { MultiFieldQueryParser parser = new MultiFieldQueryParser(Lucene.Net.Util.Version.LUCENE_29, new string[] { "id" }, analyzer); Query query = parser.Parse(mode.Content["id"]); writer.DeleteDocuments(query); }; break; default: { }; break; } } //提交操作 writer.Commit(); //优化 writer.Optimize(); //关闭连接 writer.Close(); directory.Close();
2、检索
//指定索引库文件存放文件位置 FSDirectory directory = FSDirectory.Open(new DirectoryInfo(this.IndexDir), new NativeFSLockFactory()); IndexReader reader = IndexReader.Open(directory, true); IndexSearcher searcher = new IndexSearcher(reader); //设置关键词在条件中为OR关系 BooleanQuery queryOr = new BooleanQuery(); foreach (string word in SplitContent.SplitByPanGu(keyword)) { foreach (KeyValuePair<string, string> kv in Mode.Content) { TermQuery query = new TermQuery(new Term(kv.Key, word)); //这里设置条件为Or关系 queryOr.Add(query, BooleanClause.Occur.SHOULD); } } //获取搜索结果 //1000为搜索文件的下标限制,设置这个可以控制检索的范围,也可以用于分页显示 TopDocs tds = searcher.Search(queryOr, null, 1000); ScoreDoc[] docs = tds.scoreDocs; for (int i = 0; i < docs.Length; i++) { int docId = docs[i].doc; Document doc = searcher.Doc(docId); string content = doc.Get("索引内字段的名称"); }
转自:http://www.cnblogs.com/liusuqi/p/3671161.html
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