asp.net 基于html的文件搜索引擎实现

1.引擎的实现部分（其中涉及到数据库的表的操作，这里使用的是存储过程）：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

using System.Data;
using System.Data.SqlClient;

using System.Text;
using System.Text.RegularExpressions;
using Internship.Data;

namespace Internship.WebSite
{

    public static class Searching
    {

        private static List<Entry> _Catalog = new List<Entry>();

        public static List<Entry> Catalog
        {
            get { return _Catalog; }
            set { _Catalog = value; }
        }

        public static void AddToCatalog(Entry entry)
        {
            Catalog.Add(entry);
        }
        public static void RemoveFromCatalog(Entry entry)
        {
            Catalog.Remove(entry);
        }


        static Searching()
        {
            Catalog = BuildCatalog();
        }

        public static List<Entry> Hit(String searchItem)
        {
            List<Entry> entry = new List<Entry>();

            List<Result> result = BuildResultSet(searchItem, false);
            foreach (var e in result)
                entry.Add(e.IEntry);

            return entry;
        }

        private static List<Result> BuildResultSet(string searchTerm, bool includeComments)
        {
            List<Result> results = new List<Result>();
            string term = CleanContent(searchTerm.ToLowerInvariant().Trim(), false);
            string[] terms = term.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
            string regex = string.Format(System.Globalization.CultureInfo.InvariantCulture, "({0})", string.Join("|", terms));


            foreach (Entry entry in Catalog)
            {
                Result result = new Result();
                result.Rank = 0;
                result.IEntry = entry;

                int titleMatches = Regex.Matches(entry.Title, regex).Count;
                result.Rank = titleMatches * 20;

                int postMatches = Regex.Matches(entry.Content, regex).Count;
                result.Rank += postMatches;


                if (result.Rank > 0)
                {

                    if (result.IEntry.Content.Length > 200)
                    {
                        result.IEntry.Content = result.IEntry.Content.Substring(0, 200);
                        result.IEntry.Content += "....";
                    }
                    result.IEntry.Title = Replace(result.IEntry.Title, terms);
                    result.IEntry.Content = Replace(result.IEntry.Content, terms);


                    results.Add(result);
                }
            }

            results.Sort();
            return results;
        }
        public static List<Entry> BuildCatalog()
        {
            List<Entry> entry = new List<Entry>();
            using (SqlConnection cn = new SqlConnection(InternshipSettings.WebSiteConnectionString))
            {
                SqlCommand cmd = new SqlCommand("GetAllJobPostings", cn);
                cmd.CommandType = CommandType.StoredProcedure;

                cn.Open();
                using (SqlDataReader dr = cmd.ExecuteReader())
                {
                    while (dr.Read())
                    {
                        Entry en = new Entry();
                        en.Kinds = 1;// 1 for jobposting ,2 for company instroduction
                        en.ID = dr["JobPostingID"].ToString();
                        en.Title = dr["JobPostingTitle"].ToString();
                        en.Content = dr["JobPostingText"].ToString();
                        en.PostDate = dr["JobPostingTime"].ToString();

                        en.Content = CleanContent(en.Content, true);
                        entry.Add(en);

                    }

                }

            }

            using (SqlConnection cn = new SqlConnection(InternshipSettings.WebSiteConnectionString))
            {

                SqlCommand cmd = new SqlCommand("GetAllCompanyIntroductions", cn);
                cmd.CommandType = CommandType.StoredProcedure;

                cn.Open();

                using (SqlDataReader dr = cmd.ExecuteReader())
                {
                    while (dr.Read())
                    {
                        Entry en = new Entry();
                        en.Kinds = 2; // 1 for jobposting ,2 for company instroduction
                        en.ID = dr["IntroductionID"].ToString();
                        en.Title = dr["CompanyName"].ToString();
                        en.Content = dr["Introduction"].ToString() + dr["Address"].ToString() + dr["Phone"].ToString();

                        en.Content = CleanContent(en.Content, true);
                        entry.Add(en);
                    }
                }
            }

            return entry;
        }

        private static readonly Regex STRIP_HTML = new Regex("<[^>]*>", RegexOptions.Compiled);
        /// <summary>
        /// Strips all HTML tags from the specified string.
        /// </summary>
        /// <param name="html">The string containing HTML</param>
        /// <returns>A string without HTML tags</returns>
        public static string StripHtml(string html)
        {
            if (string.IsNullOrEmpty(html))
                return string.Empty;

            return STRIP_HTML.Replace(html, " "/*string.Empty*/);
        }
        public static string CleanContent(string content, bool removeHtml)
        {
            if (removeHtml)
                content = StripHtml(content);

            content = content
                                            .Replace("//", string.Empty)
                                            .Replace("|", string.Empty)
                                            .Replace("(", string.Empty)
                                            .Replace(")", string.Empty)
                                            .Replace("[", string.Empty)
                                            .Replace("]", string.Empty)
                                            .Replace("*", string.Empty)
                                            .Replace("?", string.Empty)
                                            .Replace("}", string.Empty)
                                            .Replace("{", string.Empty)
                                            .Replace("^", string.Empty)
                                            .Replace("+", string.Empty)
                                            .Replace("", string.Empty);

            string[] words = content.Split(new char[] { ' ', '/n', '/r' }, StringSplitOptions.RemoveEmptyEntries);
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < words.Length; i++)
            {
                string word = words[i].ToLowerInvariant().Trim();
                if (word.Length > 1 /*&& !_StopWords.Contains(word)*/)
                    sb.Append(word + " ");
                //sb.Append(word);
            }

            return sb.ToString();
        }

        private static string Replace(string src, string[] terms)
        {

            foreach (var term in terms)
            {
                string replace = "<font color=/"#FF0066/">" + term + "</font>";
                src = src.Replace(term, replace);
            }
            return src;
        }
    }
}

2。如何使用？

  
            if (!string.IsNullOrEmpty(TB.Text))
            {
                CurPage = 1;
                
                entry = Searching.Hit(TB.Text);

                if (entry.Count % PAGE_SIZE == 0)
                    TolPage = entry.Count / PAGE_SIZE;
                else 
                    TolPage = entry.Count / PAGE_SIZE+1;

                DataBind(CurPage, TolPage);
            }