htmlタグ及びxpath処理に関する方法

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using System.Web;
using HtmlAgilityPack;

namespace TL.NewsGatheringService.Business.Implement
{
    /// 

    ///       
    /// 
    public class StrHelperUtil
    {
        /// 

        ///   HTML  
        /// 
        /// 
        /// 
        public static string FormatHtml(string strHtml)
        {
            //    
            strHtml = Regex.Replace(strHtml, @"]*?>.*?", "", RegexOptions.IgnoreCase);
            //  HTML
            strHtml = Regex.Replace(strHtml, @"]*)>", "", RegexOptions.IgnoreCase);
            strHtml = Regex.Replace(strHtml, @"([rn])[s]+", "", RegexOptions.IgnoreCase);
            strHtml = Regex.Replace(strHtml, @"-->", "", RegexOptions.IgnoreCase);
            strHtml = Regex.Replace(strHtml, @"