【转载】使用Lucene.NET实现数据检索功能

//指定索引库文件存放文件位置
FSDirectory directory = FSDirectory.Open(new DirectoryInfo(this.IndexDataDir), new NativeFSLockFactory());
//判断索引文件目录是否存在
bool isExist = IndexReader.IndexExists(directory);
if (isExist)
{
if (IndexWriter.IsLocked(directory))
{
IndexWriter.Unlock(directory);
}
}
//盘古分词器
PanGuAnalyzer analyzer = new PanGuAnalyzer();
//索引写入类
IndexWriter writer = new IndexWriter(directory, analyzer, !isExist, IndexWriter.MaxFieldLength.UNLIMITED);
//循环队列执行操作
while (IndexDataQueue.Count > 0)
{
Document document = new Document();
//这是我为索引数据自定义的模型类，主要内容是文件的路径、名称、内容和索引管理的操作类型（新增、更新、删除）
BaseDataMode mode = IndexDataQueue.Dequeue();
switch (mode.Type)
{
case OperationType.Insert:
{
foreach (KeyValuePair<string, string> kv in mode.Content)
{
//这里kv.Key是设置索引内字段的名称，kv.Value是这个字段内存储的内容。
document.Add(new Field(kv.Key, kv.Value, Field.Store.YES, Field.Index.ANALYZED,Field.TermVector.WITH_POSITIONS_OFFSETS));
}
writer.AddDocument(document);
}; break;
case OperationType.Update:
{
//设置删除条件
MultiFieldQueryParser parser = new MultiFieldQueryParser(Lucene.Net.Util.Version.LUCENE_29, new string[] { "id" }, analyzer);
Query query = parser.Parse(mode.Content["id"]);
writer.DeleteDocuments(query);
foreach (KeyValuePair<string, string> kv in mode.Content)
{
document.Add(new Field(kv.Key, kv.Value, Field.Store.YES, Field.Index.ANALYZED,Field.TermVector.WITH_POSITIONS_OFFSETS));
}
writer.AddDocument(document);
}; break;
case OperationType.Delete:
{
MultiFieldQueryParser parser = new MultiFieldQueryParser(Lucene.Net.Util.Version.LUCENE_29, new string[] { "id" }, analyzer);
Query query = parser.Parse(mode.Content["id"]);
writer.DeleteDocuments(query);
}; break;
default: { }; break;
}
}
//提交操作
writer.Commit();
//优化
writer.Optimize();
//关闭连接
writer.Close();
directory.Close();

//指定索引库文件存放文件位置
FSDirectory directory = FSDirectory.Open(new DirectoryInfo(this.IndexDir), new NativeFSLockFactory());
IndexReader reader = IndexReader.Open(directory, true);
IndexSearcher searcher = new IndexSearcher(reader);
//设置关键词在条件中为OR关系
BooleanQuery queryOr = new BooleanQuery();
foreach (string word in SplitContent.SplitByPanGu(keyword))
{
foreach (KeyValuePair<string, string> kv in Mode.Content)
{
TermQuery query = new TermQuery(new Term(kv.Key, word));
//这里设置条件为Or关系
queryOr.Add(query, BooleanClause.Occur.SHOULD);
}
}
//获取搜索结果
//1000为搜索文件的下标限制，设置这个可以控制检索的范围，也可以用于分页显示
TopDocs tds = searcher.Search(queryOr, null, 1000);
ScoreDoc[] docs = tds.scoreDocs;
for (int i = 0; i < docs.Length; i++)
{
int docId = docs[i].doc;
Document doc = searcher.Doc(docId);
string content = doc.Get("索引内字段的名称");
}