[英]lucene.net match if search term has no space
我正在使用lucene.net在c#asp.net应用程序的帖子中执行搜索,这是索引中的示例文档:
var doc = new Document();
var title = new Field("Title", "the album hardwired to self-destruct released", Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS);
title.Boost = 5;
doc.Add(title);
var ns_title = new Field("NoSpace_Title", "thealbumhardwiredtoselfdesctructreleased", Field.Store.NO, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS);
ns_title.Boost = 5;
doc.Add(ns_title);
doc.Add(new Field("Body", "the body text of the post", Field.Store.YES, Field.Index.ANALYZED, Field.TermVector.WITH_POSITIONS_OFFSETS));
doc.Add(new Field("Id", "1", Field.Store.YES, Field.Index.NOT_ANALYZED));
writer.AddDocument(doc);
问题 :
如果我搜索self
或destruct
或self destruct
我会受到打击。
如果我寻找selfdestruct
我不会受到打击。
搜索方法 :
var searchWords = s.Split(' ').ToList();
var directory = GetDirectory();
var reader = IndexReader.Open(directory, true);
var searcher = new IndexSearcher(reader);
var analyzer = new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30);
var parser = new MultiFieldQueryParser(Lucene.Net.Util.Version.LUCENE_30, "Title,NoSpace_Title,Body".Split(','), analyzer);
var booleanQuery = new BooleanQuery();
// Title:selfdestruct*NoSpace_Title:selfdestruct*Body:selfdestruct*
s = string.Join(" ", searchWords.Select(x => x.Contains("*") ? x : x + "*"));
Query query = parser.Parse(QueryParser.Escape(s));
query.Boost = 5;
booleanQuery.Add(query, Occur.SHOULD);
// Title:*selfdestruct*,NoSpace_Title:*selfdestruct*,Body:*selfdestruct*
// (I suppose this should work and get hit but it doesn't)
s = "*" + string.Join("", searchWords) + "*";
Query query2 = parser.Parse(QueryParser.Escape(s));
query2.Boost = 3;
booleanQuery.Add(query2, Occur.SHOULD);
// Title:selfdestruct~0.85 (fuzzy search)
s = string.Join(" ", searchWords.Select(x => x.Contains("~") ? x : x + "~0.85"));
Query query3 = parser.Parse(QueryParser.Escape(s));
booleanQuery.Add(query3, Occur.SHOULD);
var collector = TopScoreDocCollector.Create(1000, true);
searcher.Search(booleanQuery, collector);
var hits = collector.TopDocs().ScoreDocs;
var docs = hits.Select(x => searcher.Doc(x.Doc)).ToList();
您可以通过在分析仪中添加ShingleFilter来支持此功能。
ShingleFilter会将相邻的令牌合并为单个令牌,以方便搜索时不带空格。 默认情况下,它也将输出Unigram(即,还将维护单个令牌)。 因此,当您索引“ self-destruct”时,它将索引标记“ self”,“ destruct”和“ selfdestruct”。
一种无需创建自己的自定义分析器的简单方法是使用ShingleAnalyzerWrapper :
var analyzer = new ShingleAnalyzerWrapper(
new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30),
2);
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.