Sitecore searcher

c#

public static class Searcher
{
    public static List<SearchResult> DoSearch(string searchTerm)
    {
        var searchIndex = ContentSearchManager.GetIndex("MySearchIndex"); // Get the search index
        var searchPredicate = GetSearchPredicate(searchTerm); // Build the search predicate

        using (var searchContext = searchIndex.CreateSearchContext()) // Get a context of the search index
        {
            var searchResults = searchContext.GetQueryable<SearchModel>().Where(searchPredicate); // Search the index for items which match the predicate

            // This will get all of the results, which is not reccomended
            var fullResults = searchResults.GetResults();

            // This is better and will get paged results - page 1 with 10 results per page
            //var pagedResults = searchResults.Page(1, 10).GetResults();

            var myResults = new List<SearchResult>();

            foreach (var hit in fullResults.Hits)
            {
                myResults.Add(new SearchResult
                {
                    PageDescription = hit.Document.PageDescription,
                    Title = hit.Document.ItemName,
                    Url = hit.Document.Url
                });
            }

            return myResults;
        }
    }

    public static Expression<Func<SearchModel, bool>> GetSearchPredicate(string searchTerm)
    {
        var predicate = PredicateBuilder.True<SearchModel>(); // Items which meet the predicate

        // Search the whole phrase - LIKE
        predicate = predicate.Or(x => x.DispalyName.Like(searchTerm)).Boost(1.2f);
        predicate = predicate.Or(x => x.PageDescription.Like(searchTerm)).Boost(1.2f);
        predicate = predicate.Or(x => x.Introduction.Like(searchTerm)).Boost(1.2f);
        predicate = predicate.Or(x => x.Maintext.Like(searchTerm)).Boost(1.2f);

        // Search the whole phrase - CONTAINS
        predicate = predicate.Or(x => x.DispalyName.Contains(searchTerm)).Boost(2.0f);
        predicate = predicate.Or(x => x.PageDescription.Contains(searchTerm)).Boost(2.0f);
        predicate = predicate.Or(x => x.Introduction.Contains(searchTerm)).Boost(2.0f);
        predicate = predicate.Or(x => x.Maintext.Contains(searchTerm)).Boost(2.0f);

        // Search the individual words
        foreach (var t in searchTerm.Split(' '))
        {
            var tempTerm = t;

            predicate = predicate.Or(x => x.DispalyName.Contains(t)).Boost(1.0f);
            predicate = predicate.Or(x => x.PageDescription.Contains(t)).Boost(1.0f);
            predicate = predicate.Or(x => x.Introduction.Contains(t)).Boost(1.0f);
            predicate = predicate.Or(x => x.Maintext.Contains(t)).Boost(1.0f);
        }

        return predicate;
    }

    /// <summary>
    /// Search item mapped to Lucene index
    /// </summary>
    public class SearchModel
    {
        [IndexField("_name")]
        public string ItemName { get; set; }

        [IndexField("_displayname")]
        public string DispalyName { get; set; }

        [IndexField("_templatename")]
        public string TemplateName { get; set; }

        [IndexField("urllink")]
        public string Url { get; set; }

        [IndexField("page_description")]
        public string PageDescription { get; set; }

        [IndexField("introduction")]
        public string Introduction { get; set; }

        [IndexField("text")]
        public string Maintext { get; set; }
    }

    /// <summary>
    /// Custom search result model for binding to front end
    /// </summary>
    public class SearchResult
    {
        public string Title { get; set; }

        public string Url { get; set; }

        public string PageDescription { get; set; }
    }
}