1         /// <summary>

 2         /// 创建索引

 3         /// </summary>

 4         private void CreateIndex()

 5         {

 6             //索引的文件存放的路径

 7             string indexPath = @"\Lucene";

 8

 9             //FSDirectory是用于对文件系统目录的操作的类

10             FSDirectory directory = FSDirectory.Open(new DirectoryInfo(indexPath), new NativeFSLockFactory());

11             //检查目录是否存在

12             bool isUpdate = IndexReader.IndexExists(directory);

13

14             if (isUpdate)

15             {

16                 //目录存在则判断目录是否被锁定，被锁定就解锁

17                 if (IndexWriter.IsLocked(directory))

18                 {

19                     IndexWriter.Unlock(directory);

20                 }

21             }

22             //IndexWriter主要用于写索引

23             //方法签名：public IndexWriter(Directory d,Analyzer a,boolean create,IndexWriter.MaxFieldLength mfl)

24             //第一个参数是 (Directory d)：索引的目录(前面的FSDirectory类的对象)

25             //第二个参数是 (Analyzer a)：分析器(这里我们用盘古分词的分析器)

26             //第三个参数是 (boolean create)：是否创建目录

27             //第四个参数是 (IndexWriter.MaxFieldLength):最大长度

28             IndexWriter writer = new IndexWriter(directory, new PanGuAnalyzer(), !isUpdate,

29                 IndexWriter.MaxFieldLength.UNLIMITED);

30

31             //BLL层的一个类，用于对表T_Article进行操作

32             //T_Article表中有三个字段: Id   Title  Message

33             T_ArticleBLL bll = new T_ArticleBLL();

34

35             //遍历T_Article表中的内容

36             foreach (T_Articles art in bll.GetAll())

37             {

38                 writer.DeleteDocuments(new Term("id", art.ID.ToString()));

39

40                 //Document文档对象

41                 Document document = new Document();

42

43                 //将T_Articles表中的内容写入索引

44                 document.Add(new Field("id", art.ID.ToString(), Field.Store.YES, Field.Index.NOT_ANALYZED));

45

46                 document.Add(new Field("title", art.Title, Field.Store.YES, Field.Index.ANALYZED,

47                     Field.TermVector.WITH_POSITIONS_OFFSETS));

48

49                 document.Add(new Field("msg", art.Message, Field.Store.YES, Field.Index.ANALYZED,

50                     Field.TermVector.WITH_POSITIONS_OFFSETS));

51                 writer.AddDocument(document);

52             }

53             //要记得关闭

54             writer.Close();

55             directory.Close();

56         }