Sitecore search context highlighting

C#

/// <summary>
/// Highlight search term
/// </summary>
/// <param name="searchTerm">Search term</param>
/// <param name="searchContent">search content</param>
/// <returns>Search content with highlighted search term</returns>
private static string HighlightSearchTerm(string searchTerm, string searchContent)
{
    // create analyzer
    var analyzer = new StandardAnalyzer(Lucene.Net.Util.Version.LUCENE_30);

    // create FuzzyQuery using the BooleanQuery for multiple words
    var booleanQuery = new BooleanQuery();
    var segments = searchTerm.ToLower().Split(new[] { " " }, StringSplitOptions.RemoveEmptyEntries);
    foreach (var segment in segments)
    {
        var fuzzyQuery = new FuzzyQuery(new Term("", segment), 0.7f, 3);
        booleanQuery.Add(new BooleanClause(fuzzyQuery, Occur.SHOULD));
    }
    // create highlighter - using strong tag to highlight in this case (change as needed)
    IFormatter formatter = new SimpleHTMLFormatter("<strong>", "</strong>");

    // excerpt set to 200 characters in length
    var fragmenter = new SimpleFragmenter(200);
    var scorer = new QueryScorer(booleanQuery);
    var highlighter = new Highlighter(formatter, scorer) { TextFragmenter = fragmenter };

    // optional step to remove html tags from content
    string rawPageContent = Sitecore.StringUtil.RemoveTags(searchContent);

    // get highlighted fragment
    Lucene.Net.Analysis.TokenStream stream = analyzer.TokenStream("", new StringReader(rawPageContent));
    string highlightedFragment = highlighter.GetBestFragment(stream, rawPageContent);

    if (highlightedFragment == null)
    {
        // null is returned if no matching text found
        return searchContent;
    }

    return highlightedFragment;
}