如何使用LuceneNet中的indexWriter删除文档

Question

我有这个方法,我在我的控制器中调用,必须删除一个特定的文档.我在一些文章中读到删除文档的最佳方法是使用IndexWriter.但我不能让它发挥作用.这是我的代码

我的索引:

    var article1 = new Document();
               article1.Add(new Field("Id", "1", Field.Store.YES, Field.Index.ANALYZED));
               article1.Add(new Field("Author", "Author", Field.Store.YES, Field.Index.ANALYZED));
               article1.Add(new Field("Title", "Title", Field.Store.YES, Field.Index.ANALYZED));

  var directory = FSDirectory.Open(new DirectoryInfo(IndexRoute));
           var analyzar = new StandardAnalyzer(Version.LUCENE_29);

           var writer = new IndexWriter(directory, analyzar, true,  IndexWriter.MaxFieldLength.LIMITED);

           writer.AddDocument(article1);
           writer.Optimize();
           writer.Commit();
           writer.Close();

方法删除:

public void Delete(string id)
{
    var directory = FSDirectory.Open(new DirectoryInfo(IndexRoute));
    var analyzar = new StandardAnalyzer(Version.LUCENE_29);
    var writer = new IndexWriter(directory, analyzar, true, IndexWriter.MaxFieldLength.LIMITED);
    var term = new Term("Id", id);
    writer.DeleteDocuments(term);
    writer.Optimize();
    writer.Commit();
    writer.Close();
}

控制器中调用"删除"void的方法:

  public ActionResult Delete()
    {
        _carService.Delete("1");
        return RedirectToAction("Index", "Home");
    }

所以我找不到我的错误,请帮助...

Answer 1

当您为删除方法构建IndexWriter时,如下所示:

new IndexWriter(directory, analyzar, true, IndexWriter.MaxFieldLength.LIMITED);

您为create参数指定true,该参数将使用空索引覆盖现有索引,并删除所有文档.

Answer 2

这是因为您将 id 字段存储为Field.Index.ANALYZED，您应该始终将 id 字段存储为Field.Index.NOT_ANALYZED，这样这些字段就不会被标记化并按原样存储在索引中。对于您不想在索引时更改的其他字段也是如此。