1、1. 基本應用 using System;using System.Collect ion s.Ge neric;using System.Text;using Luce ne.Net;using Luce ne.Net.A nalysis;using Luce ne.Net.A nalysis.Sta ndard;using Luce ne.Net.Docume nts;using Luce ne.Net.l ndex;using Luce ne.Net.QueryParsers;using Luce ne.Net.Search;using Luce ne.Net.Store;using L

2、uce ne.Net.Util;n amespace Con soleApplicati on 1.Luce nepublic class Luce neTestprivate const stri ng FieldName =a?name ;private const string FieldValue =value ;private Directory directory = new RAMDirectory();private An alyzer an alyzer = new Stan dardA nalyzer();public Luce neTest()private void I

3、n dex()In dexWriter writer = new In dexWriter(directory, an alyzer, true);writer.maxFieldLe ngth = 1000;for (int i = 1; i <= 100; i+)Docume nt docume nt = new Docume nt();document.Add(new Field(FieldName,name ” + i, Field.Store.YES,Field.I ndex.UN_TOKENIZED);docume nt.Add( new Field(FieldValue,He

4、llo, World! ”，Field.Store.YES,Field .In dex.TOKENIZED);writer.AddDocume nt(docume nt);writer.Optimize();writer.Close();private void Search()Query query = QueryParser.Parse( name* ”，FieldName, analyzer);In dexSearcher searcher = new In dexSearcher(directory);Hits hits = searcher.Search(query);Console

5、.WriteLine(符合條件記錄：0;索引庫記錄總數：1 ”, hits.Length(),searcher.Reader.NumDocs();for (int i = 0; i < hits.Le ngth(); i+)int docId = hits .I d(i);string name = hits.Doc(i).Get(FieldName);stri ng value = hits.Doc(i).Get(FieldValue);float score = hits.Score(i);Co nsole.WriteL in e(0: DocId:1; Name:2; Value:

6、3; Score:4 ”，i + 1, docId, n ame, value, score);searcher.Close();除了 RAMDirectory ,還可以使用 FSDirectory。(注意 FSDirectory .GetDirectory 的 create 參數，為true時將刪除已有索引庫文件， 可以通過IndexReader.IndexExists() 方法判斷。) 從指定目錄打開已有索引庫。private Directory directory = FSDirectory.GetDirectory(c：index ”，false);將索引庫載入內存，以提高搜索速度。p

7、rivate Directory directory = new RAMDirectory(FSDirectory.GetDirectory("c:index ”，false);/或/private Directory directory = new RAMDirectory(c:in dex");2. 多字段搜索使用MultiFieldQueryParser可以指定多個搜索字段。Query query = MultiFieldQueryParser.Parse( name* ”new string FieldName,FieldValue , an alyzer);In

8、dexReader reader = In dexReader.Ope n( directory);In dexSearcher searcher = new In dexSearcher(reader);Hits hits = searcher.Search(query);3. 多條件搜索除了使用QueryParser.Parse分解復雜的搜索語法外，還可以通過組合多個Query來達到目的。hame1 "); /詞語搜索name*"); / 通配符name1 "); /字段搜索Query query1 = new TermQuery (new Term(Fiel

9、dValue,Query query2 = new WildcardQuery (new Term(FieldName,/Query query3 = new PrefixQuery (new Term(FieldName, Field:Keyword，自動在結尾添加* /Query query4 = new Ran geQuery (new Term(FieldNumber,NumberTools.LongT oString(1 1L), new Term(FieldNumber,NumberTools.LongT oString(13L), true); / 范圍搜索/Query quer

10、y5 = new FilteredQuery(query, filter); /帶過濾條件的搜索Boolea nQuery query = new Boolea nQuery();query.Add(query1, Boolea nClause.Occur.MUST);query.Add(query2, Boolea nClause.Occur.MUST);In dexSearcher searcher = new In dexSearcher(reader);Hits hits = searcher.Search(query);4. 設置權重可以給Document和Field增加權重(Boo

11、st)，使其在搜索結果排名更加靠前。缺省情況下，搜索結果以Document.Score作為排序依據，該數值越大排名越靠前。Boost缺省值為1。Score = Score * Boost通過上面的公式，我們就可以設置不同的權重來影響排名。如下面的例子中根據VIP級別設定不同的權重。Docume nt docume nt = new Docume nt();switch (vip)case VIP .Gold: document.SetBoost(2F); break;case VIP .Argentine: document.SetBoost(1.5F); break;只要Boost足夠大，那

12、么就可以讓某個命中結果永遠排第一位，這就是百度等網站的”收費排名”業務。明顯有失公平，鄙視一把。5. 排序通過SortField的構造參數，我們可以設置排序字段，排序條件，以及倒排。Sort sort = new Sort( new SortField(FieldName, SortField.DOC, false);In dexSearcher searcher = new In dexSearcher(reader);Hits hits = searcher.Search(query, sort);排序對搜索速度影響還是很大的，盡可能不要使用多個排序條件。6. 過濾使用Filter對搜索結

13、果進行過濾，可以獲得更小范圍內更精確的結果。舉個例子，我們搜索上架時間在2005-10-1至U 2005-10-30 之間的商品。對于日期時間，我們需要轉換一下才能添加到索引庫，同時還必須是索引字段。/indexdocument.Add(FieldDate, DateField.DateToString(date), Field.Store.YES,Field.I ndex.UN_TOKENIZED);/ searchFilter filter = new DateFilter(FieldDate, DateTime.Parse(2005-10-1 ”)，DateTime.Parse( 200

14、5-10-30 )；Hits hits = searcher.Search(query, filter);除了日期時間，還可以使用整數。比如搜索價格在100 200 之間的商品。Luce ne.Net NumberTools對于數字進行了補位處理，如果需要使用浮點數可以自己參考源碼進行。/indexdocument.Add(new Field(FieldNumber, NumberTools.LongToString(long)price), Field.Store.YES, Fieldn dex.UN_TOKENIZED);/ searchFilter filter = new Ra nge

15、Filter(FieldNumber, NumberTools.Lo ngToStri ng(100L),NumberTools.LongT oString(200L), true, true);Hits hits = searcher.Search(query, filter);使用Query作為過濾條件。QueryFilter filter = new QueryFilter(QueryParser.Parse(name2 ",FieldValue, analyzer);我們還可以使用FilteredQuery進行多條件過濾。Filter filter = new DateFil

16、ter(FieldDate, DateTime.Parse(2005-10-10 ”)，DateTime.Parse( 2005-10-15 )；Filter filter2 = new Ran geFilter(FieldNumber, NumberTools.L on gToStri ng(11L),NumberTools.LongT oString(13L), true, true);Query query = QueryParser.Parse(name* ”，FieldName, analyzer);query = new FilteredQuery(query, filter);q

17、uery = new FilteredQuery(query, filter2);In dexSearcher searcher = new In dexSearcher(reader);Hits hits = searcher.Search(query);7. 分布搜索我們可以使用 MultiReader 或MultiSearcher 搜索多個索引庫。MultiReader reader = new MultiReader( new In dexReader IndexReader.Open("c:index "),1 ndexReader.Open("serv

18、erindex ");In dexSearcher searcher = new In dexSearcher(reader);Hits hits = searcher.Search(query);或In dexSearcher searcher1 = new In dexSearcher(reader1);In dexSearcher searcher2 = new In dexSearcher(reader2);MultiSearcher searcher = new MultiSearcher( new Searchable searcher1, searcher2 );Hit

19、s hits = searcher.Search(query);還可以使用 ParallelMultiSearcher進行多線程并行搜索。8. 合并索引庫將 directory1 合并到 directory2 中。Directory directory1 = FSDirectory.GetDirectory(ihdex1 ",false);Directory directory2 = FSDirectory.GetDirectory(ihdex2 ",false);IndexWriter writer = new IndexWriter(directory2, analyz

20、er, false);writer.Add In dexes (new Directory directory );Co nsole.WriteL in e(writer.DocCou nt();writer.Close();9. 顯示搜索語法字符串我們組合了很多種搜索條件，或許想看看與其對等的搜索語法串是什么樣的。Boolea nQuery query = new Boolea nQuery();query.Add(query1, true, false);query.Add(query2, true, false);/Console.WriteLine(Syntax: 0 ”，query.ToString();輸出：Sy ntax: +(name:n ame* value: name*) +nu mber:0000000000000000b TO0000000000000000d呵呵，就這么簡單。10. 操作索引庫刪除(軟刪除，僅添加了刪除標記。調用IndexWriter.Optimize()后真正刪除。)In dexReader reader = In dexReader.Ope n( directory);/刪除指定序號(DocId)的 Document 。reader.Delete(123);II刪除包含指定 Te