예제 #1
0
        public SearchModel Search(string searchText)
        {
            var result = new SearchModel();

            if (string.IsNullOrEmpty(searchText))
            {
                result.Message = "Įveskite paieškos užklausą.";
                return(result);
            }

            var stemmedSearchText = new LithuanianStemmer().Stem(searchText.Trim());

            if (string.IsNullOrEmpty(stemmedSearchText))
            {
                result.Message = "Įveskite paieškos užklausą.";
                return(result);
            }

            Lucene.Net.Search.Hits hits = null;
            try
            {
                if (char.IsLetter(stemmedSearchText[stemmedSearchText.Length - 1]))
                {
                    stemmedSearchText += "*";
                }

                query = parser.Parse(stemmedSearchText);

                if (searcher == null)
                {
                    searcher = new Lucene.Net.Search.IndexSearcher(CustomAppSettings.SearchIndexFolder);
                }

                hits = searcher.Search(query);
            }
            catch (Exception e)
            {
                result.Message = "Paieška nepavyko. Pataisykite užklausą. Klaidos pranešimas: " + e.Message;
                return(result);
            }

            Lucene.Net.Highlight.Formatter formatter = new Lucene.Net.Highlight.SimpleHTMLFormatter(
                "<span class=\"highlightResult\">",
                "</span>");

            var fragmenter  = new Lucene.Net.Highlight.SimpleFragmenter(100);
            var scorer      = new Lucene.Net.Highlight.QueryScorer(searcher.Rewrite(query));
            var highlighter = new Lucene.Net.Highlight.Highlighter(formatter, scorer);

            highlighter.SetTextFragmenter(fragmenter);

            Dictionary <string, int> dict_already_seen_ids = new Dictionary <string, int>();

            var list = new List <SearchIndexModel>();

            // insert the search results into a temp table which we will join with what's in the database
            for (int i = 0; i < hits.Length(); i++)
            {
                if (dict_already_seen_ids.Count < 100)
                {
                    Lucene.Net.Documents.Document doc = hits.Doc(i);
                    string id = doc.Get("id");
                    if (!dict_already_seen_ids.ContainsKey(id))
                    {
                        dict_already_seen_ids[id] = 1;
                        var model = new SearchIndexModel();
                        model.Id      = id;
                        model.Score   = hits.Score(i);
                        model.Subject = doc.Get("subject");
                        model.Type    = (EntryTypes)Enum.Parse(typeof(EntryTypes), doc.Get("type"));

                        string raw_text = HttpUtility.HtmlEncode(doc.Get("raw_text"));
                        //string raw_text = doc.Get("raw_text");

                        Lucene.Net.Analysis.TokenStream stream = analyzer.TokenStream("text",
                                                                                      new System.IO.StringReader(
                                                                                          raw_text));
                        string highlighted_text = highlighter.GetBestFragments(stream, raw_text, 3, "...").Replace("'",
                                                                                                                   "''");


                        if (highlighted_text == "") // someties the highlighter fails to emit text...
                        {
                            highlighted_text = raw_text.Replace("'", "''");
                        }
                        if (highlighted_text.Length > 3000)
                        {
                            highlighted_text = highlighted_text.Substring(0, 3000);
                        }

                        model.HighlightedText = highlighted_text;

                        list.Add(model);
                    }
                }
                else
                {
                    break;
                }
            }

            result.List         = list;
            result.SearchPhrase = searchText;
            if (list.Count == 0)
            {
                result.Message = string.Format("Įrašų pagal užklausą '{0}' nerasta. Patikslinkite paieškos duomenis.", searchText);
            }

            return(result);
        }