c# - Lucene.net 字段包含多个值和搜索对象

Question

任何人都知道在包含多个值的字段上搜索的最佳方法是什么？

string tagString = "";
foreach(var tag in tags)
{
    tagString = tagString += ":" + tag;
}
doc.Field(new Field("Tags", tagString, Field.Store.YES, Field.Index.Analyzed);

假设我想搜索所有带有“csharp”标签的文档，我最能实现这个？

Answer 1

我认为您正在寻找的是将多个具有相同名称的字段添加到单个Document.

您所做的是创建一个Document并向其添加多个标签Field。

RAMDirectory ramDir = new RAMDirectory();

IndexWriter writer = new IndexWriter(ramDir, new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_29));


Document doc = new Document();
Field tags = null;

string [] articleTags = new string[] {"C#", "WPF", "Lucene" };
foreach (string tag in articleTags)
{   
    // adds a field with same name multiple times to the same document
    tags = new Field("tags", tag, Field.Store.YES, Field.Index.NOT_ANALYZED);
    doc.Add(tags);
}

writer.AddDocument(doc);
writer.Commit();

// search
IndexReader reader = writer.GetReader();
IndexSearcher searcher = new IndexSearcher(reader);

// use an analyzer that treats the tags field as a Keyword (Not Analyzed)
PerFieldAnalyzerWrapper aw = new PerFieldAnalyzerWrapper(new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_29));
aw.AddAnalyzer("tags", new KeywordAnalyzer());

QueryParser qp = new QueryParser(Lucene.Net.Util.Version.LUCENE_29, "tags", aw);

Query q = qp.Parse("+WPF +Lucene");
TopDocs docs = searcher.Search(q, null, 100);
Console.WriteLine(docs.totalHits); // 1 hit

q = qp.Parse("+WCF +Lucene");
docs = searcher.Search(q, null, 100);
Console.WriteLine(docs.totalHits); // 0 hit