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Lucene.net应用

1、加入盘古分词方法

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  /// <summary>       /// 对输入的搜索的条件进行分词       /// </summary>       /// <param name="str"></param>       /// <returns></returns>       public static List<string> GetPanGuWord(string str)       {           Analyzer analyzer = new PanGuAnalyzer();           TokenStream tokenStream = analyzer.TokenStream("", new StringReader(str));           Lucene.Net.Analysis.Token token = null;           List<string> list = new List<string>();           while ((token = tokenStream.Next()) != null)           {              list.Add(token.TermText());           }           return list;       }
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2、创建视图显示的MODEL(ViewModel)

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using System;using System.Collections.Generic;using System.Linq;using System.Web;namespace CZBK.ItcastOA.WebApp.Models{    public class ViewSarchContentModel    {        public string Id { get; set; }        public string Title { get; set; }        public string Content { get; set; }    }}
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3、根据数据库表中字段创建索引

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       /// <summary>        /// 负责向写数据        /// </summary>        private void CreateSearchIndex()        {            string indexPath = @"C:\lucenedir";//注意和磁盘上文件夹的大小写一致,否则会报错。将创建的分词内容放在该目录下。            FSDirectory directory = FSDirectory.Open(new DirectoryInfo(indexPath), new NativeFSLockFactory());//指定索引文件(打开索引目录) FS指的是就是FileSystem            bool isUpdate = IndexReader.IndexExists(directory);//IndexReader:对索引进行读取的类。该语句的作用:判断索引库文件夹是否存在以及索引特征文件是否存在。            if (isUpdate)            {                //同时只能有一段代码对索引库进行写操作。当使用IndexWriter打开directory时会自动对索引库文件上锁。                //如果索引目录被锁定(比如索引过程中程序异常退出),则首先解锁(提示一下:如果我现在正在写着已经加锁了,但是还没有写完,这时候又来一个请求,那么不就解锁了吗?这个问题后面会解决)                if (IndexWriter.IsLocked(directory))                {                    IndexWriter.Unlock(directory);                }            }            IndexWriter writer = new IndexWriter(directory, new PanGuAnalyzer(), !isUpdate, Lucene.Net.Index.IndexWriter.MaxFieldLength.UNLIMITED);//向索引库中写索引。这时在这里加锁。           List<Books>list= BookService.LoadEntities(c=>true).ToList();           foreach (Books bookModel in list)           {               writer.DeleteDocuments(new Term("Id",bookModel.Id.ToString()));               Document document = new Document();//表示一篇文档。               //Field.Store.YES:表示是否存储原值。只有当Field.Store.YES在后面才能用doc.Get("number")取出值来.Field.Index. NOT_ANALYZED:不进行分词保存               document.Add(new Field("Id",bookModel.Id.ToString(), Field.Store.YES, Field.Index.NOT_ANALYZED));               //Field.Index. ANALYZED:进行分词保存:也就是要进行全文的字段要设置分词 保存(因为要进行模糊查询)               //Lucene.Net.Documents.Field.TermVector.WITH_POSITIONS_OFFSETS:不仅保存分词还保存分词的距离。               document.Add(new Field("Title", bookModel.Title, Field.Store.YES, Field.Index.ANALYZED, Lucene.Net.Documents.Field.TermVector.WITH_POSITIONS_OFFSETS));               document.Add(new Field("Content", bookModel.ContentDescription, Field.Store.YES, Field.Index.ANALYZED, Lucene.Net.Documents.Field.TermVector.WITH_POSITIONS_OFFSETS));               writer.AddDocument(document);           }                        writer.Close();//会自动解锁。            directory.Close();//不要忘了Close,否则索引结果搜不到        }
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4、搜索

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       private List<ViewSarchContentModel> SearchBookContent()        {            string indexPath = @"C:\lucenedir";            List<string> kw =Common.WebCommon.GetPanGuWord(Request["txtContent"]);            FSDirectory directory = FSDirectory.Open(new DirectoryInfo(indexPath), new NoLockFactory());            IndexReader reader = IndexReader.Open(directory, true);            IndexSearcher searcher = new IndexSearcher(reader);            //搜索条件            PhraseQuery query = new PhraseQuery();            foreach (string word in kw)//先用空格,让用户去分词,空格分隔的就是词“计算机   专业”            {                query.Add(new Term("Content", word));            }            //query.Add(new Term("body","语言"));--可以添加查询条件,两者是add关系.顺序没有关系.            //query.Add(new Term("body", "大学生"));            //query.Add(new Term("body", kw));//body中含有kw的文章            query.SetSlop(100);//多个查询条件的词之间的最大距离.在文章中相隔太远 也就无意义.(例如 “大学生”这个查询条件和"简历"这个查询条件之间如果间隔的词太多也就没有意义了。)            //TopScoreDocCollector是盛放查询结果的容器            TopScoreDocCollector collector = TopScoreDocCollector.create(1000, true);            searcher.Search(query, null, collector);//根据query查询条件进行查询,查询结果放入collector容器            ScoreDoc[] docs = collector.TopDocs(0, collector.GetTotalHits()).scoreDocs;//得到所有查询结果中的文档,GetTotalHits():表示总条数   TopDocs(300, 20);//表示得到300(从300开始),到320(结束)的文档内容.            //可以用来实现分页功能            List<ViewSarchContentModel> list = new List<ViewSarchContentModel>();            for (int i = 0; i < docs.Length; i++)            {                ViewSarchContentModel viewModel = new ViewSarchContentModel();                //                //搜索ScoreDoc[]只能获得文档的id,这样不会把查询结果的Document一次性加载到内存中。降低了内存压力,需要获得文档的详细内容的时候通过searcher.Doc来根据文档id来获得文档的详细内容对象Document.                                                int docId = docs[i].doc;//得到查询结果文档的id(Lucene内部分配的id)                Document doc = searcher.Doc(docId);//找到文档id对应的文档详细信息                viewModel.Id = doc.Get("Id");                viewModel.Title = doc.Get("Title");                viewModel.Content =Common.WebCommon.CreateHightLight(Request["txtContent"], doc.Get("Content"));//搜索内容关键字高亮显示                list.Add(viewModel);                            }            return list;        }
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5、返回给VIEW

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 public ActionResult SearchContent()        {            if (!string.IsNullOrEmpty(Request["btnSearch"]))            {               List<ViewSarchContentModel>list= SearchBookContent();               ViewData["searchList"] = list;               ViewData["searchWhere"] = Request["txtContent"];               return View("Index");            }            else            {                CreateSearchIndex();            }            return Content("ok");        }
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6、视图表现

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@{    Layout = null;}@using CZBK.ItcastOA.WebApp.Models<!DOCTYPE html><html><head>    <meta name="viewport" content="width=device-width" />    <title>文档搜索</title>    <script src="~/Scripts/jquery-1.7.1.min.js"></script>    <style type="text/css">      .search-text2{ display:block; width:528px; height:26px; line-height:26px; float:left; margin:3px 5px; border:1px solid; font-family:‘Microsoft Yahei‘; font-size:14px;}      .search-btn2{width:102px; height:32px; line-height:32px; cursor:pointer; border:0px; background-color:#d6000f;font-family:‘Microsoft Yahei‘; font-size:16px;color:#f3f3f3;}      .search-list{width:600px; overflow:hidden; margin:10px 20px 0px 20px;}       .search-list dt{font-family:‘Microsoft Yahei‘; font-size:16px; line-height:20px; margin-bottom:7px; font-weight:normal;}       .search-list .search-detail{font-size:12px; color:#666666;margin-bottom:5px; font-family:Arial;line-height:16px;}       .search-list dt a{color:#2981a9;}    </style> </head><body>      <!-- JiaThis Button BEGIN --><script type="text/javascript" >    var jiathis_config = {        data_track_clickback: true,        showClose: true,        hideMore: false    }</script><script type="text/javascript" src="http://v3.jiathis.com/code/jiathis_r.js?uid=1986459&type=left&btn=l.gif&move=0" charset="utf-8"></script><!-- JiaThis Button END -->    <div>        <form method="get" action="/Search/SearchContent">            <input type="text" value="@ViewData["searchWhere"]" name="txtContent" autocomplete="off" class="search-text2"/>            <input type="submit" value="搜一搜" name="btnSearch" class="search-btn2" />            <input type="submit" value="创建索引库" name="btnCreate" />        </form>        <dl class="search-list">        @if (ViewData["searchList"] != null)        {            foreach (ViewSarchContentModel viewModel in (List<ViewSarchContentModel>)ViewData["searchList"])            {                <dt><a href="/Book/ShowDetail/?id=@viewModel.Id"> @viewModel.Title</a></dt>             <dd class="search-detail">@MvcHtmlString.Create(viewModel.Content)</dd>            }        }            </dl>    </div></body></html>
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改变输入框、按钮样式,高亮显示

 <style type="text/css">      .search-text2{ display:block; width:528px; height:26px; line-height:26px; float:left; margin:3px 5px; border:1px solid; font-family:‘Microsoft Yahei‘; font-size:14px;}      .search-btn2{width:102px; height:32px; line-height:32px; cursor:pointer; border:0px; background-color:#d6000f;font-family:‘Microsoft Yahei‘; font-size:16px;color:#f3f3f3;}      .search-list{width:600px; overflow:hidden; margin:10px 20px 0px 20px;}       .search-list dt{font-family:‘Microsoft Yahei‘; font-size:16px; line-height:20px; margin-bottom:7px; font-weight:normal;}       .search-list .search-detail{font-size:12px; color:#666666;margin-bottom:5px; font-family:Arial;line-height:16px;}       .search-list dt a{color:#2981a9;}    </style>

盘古分词的高亮组件PanGu.HighLight.dll,引用高亮显示组件

    // /创建HTMLFormatter,参数为高亮单词的前后缀       public static string CreateHightLight(string keywords, string Content)       {           PanGu.HighLight.SimpleHTMLFormatter simpleHTMLFormatter =            new PanGu.HighLight.SimpleHTMLFormatter("<font color=\"red\">", "</font>");           //创建Highlighter ,输入HTMLFormatter 和盘古分词对象Semgent           PanGu.HighLight.Highlighter highlighter =           new PanGu.HighLight.Highlighter(simpleHTMLFormatter,           new Segment());           //设置每个摘要段的字符数           highlighter.FragmentSize = 150;           //获取最匹配的摘要段           return highlighter.GetBestFragment(keywords, Content);       }

keywords搜索关键词,Content搜索结果

 viewModel.Content =Common.WebCommon.CreateHightLight(Request["txtContent"], doc.Get("Content"));//搜索内容关键字高亮显示

视图中

<dd class="search-detail">@MvcHtmlString.Create(viewModel.Content)</dd>

@输出进行了编码,用@会输出HTML标签

Lucene每次生成索引不会删除、覆盖以前生成的,会造成搜索时搜索到重复的记录,所以生成前先要删除一次(实质没有删除文件,只是给文件个删除标记)

writer.DeleteDocuments(new Term("Id",bookModel.Id.ToString()));

 

搜索页面采用<form method="get" .............>,并采用静态页面:有利于网站推广

 

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加<script src="http://www.mamicode.com/~/Scripts/jquery-1.7.1.min.js"></script>

并将以下代码放入body
<!-- JiaThis Button BEGIN -->
<script type="text/javascript" >
var jiathis_config = {
data_track_clickback: true,
showClose: true,
hideMore: false
}
</script>
<script type="text/javascript" src="http://v3.jiathis.com/code/jiathis_r.js?uid=1986459&type=left&btn=l.gif&move=0" charset="utf-8"></script>
<!-- JiaThis Button END -->

Lucene.net应用