lucene.net 结合了多个过滤器并且没有搜索词 [英] lucene.net combine multiple filters and no search terms

问题描述

如何在 Lucene.Net 中跨多个字段进行过滤?在一个领域我只是这样做:

How can I do a Filter across multiple fields in Lucene.Net? On one field I simply do:

TermQuery tool = new TermQuery(new Term("Tool", "Nail"));
Filter f = new QueryFilter(tool);

如果我现在想为过滤器添加指甲长度，我该怎么做?

If I now wanted to add a nail length to the filter, how can I do that?

另外，我希望用户能够在没有搜索词的情况下进行搜索(即只需选择一个类别)，我该怎么做?

Also, I want the user to be a able to do a search with no search term (i.e. by just choosing a category) how can I do that?

推荐答案

我想你在问两个问题...

I think you're asking two questions...

问题 1:添加额外的过滤器

请记住，QueryFilter 接受 any 查询(不仅仅是 TermQuery).因此，您可以创建一个 BooleanQuery 您希望过滤的条件.

Remember, QueryFilter accepts any query (not just TermQuery). Therefore, you can create a BooleanQuery of the criteria you wish to filter on.

TermQuery toolQuery = new TermQuery(new Term("Tool", "Nail"));
TermQuery nailLengthQuery = new TermQuery(new Term("NailLength", "3 inches"));

BooleanQuery filterQuery = new BooleanQuery();
filterQuery.add(toolQuery, BooleanClause.Occur.MUST);
filterQuery.add(nailLengthQuery, BooleanClause.Occur.MUST);

Filter f = new QueryFilter(filterQuery);

问题 2:不使用搜索词进行搜索

如果用户没有提供搜索词，您可以使用 MatchAllDocsQuery 查询进行搜索.

If the user provides no search term, you can search using a MatchAllDocsQuery query.

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