常用编缉html方法

 public class SubHtmlString
    {
        /// <summary>
        /// 去除HTML标记
        /// </summary>
        /// <param name="NoHTML">包括HTML的源码 </param>
        /// <returns>已经去除后的文字</returns>
        public static string NoHTML(string Htmlstring)
        {
            if (Htmlstring == null)
                return "";
            //删除脚本
            Htmlstring = Regex.Replace(Htmlstring, @"<script[^>]*?>.*?</script>", "", RegexOptions.IgnoreCase);
            //删除HTML
            Htmlstring = Regex.Replace(Htmlstring, @"<(.[^>]*)>", "", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"([/r/n])[/s]+", "", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"-->", "", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"<!--.*", "", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(quot|#34);", "/"", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(amp|#38);", "&", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(lt|#60);", "<", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(gt|#62);", ">", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(nbsp|#160);", " ", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(iexcl|#161);", "/xa1", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(cent|#162);", "/xa2", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(pound|#163);", "/xa3", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&(copy|#169);", "/xa9", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&#(/d+);", "", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&ldquo;", "“", RegexOptions.IgnoreCase);
            Htmlstring = Regex.Replace(Htmlstring, @"&rdquo;", "”", RegexOptions.IgnoreCase);
            Htmlstring.Replace("<", "");
            Htmlstring.Replace(">", "");
            Htmlstring.Replace("/r/n", "");
            Htmlstring = System.Web.HttpContext.Current.Server.HtmlEncode(Htmlstring).Trim();
            return Htmlstring;

        }

        /// <summary>
        /// 去除HTML标记,提取HTML代码中文字的C#函数
        /// </summary>
        /// <param name="strHtml">包括HTML的源码 </param>
        /// <returns>已经去除后的文字</returns>
        public static string StripHTML(string strHtml)
        {

            string[] aryReg ={
          @"<script[^>]*?>.*?</script>",
          @"<(///s*)?!?((/w+:)?/w+)(/w+(/s*=?/s*(([""'])(//[""'tbnr]|[^/7])*?/7|/w+)|.{0})|/s)*?(///s*)?>",
          @"([/r/n])[/s]+",
          @"&(quot|#34);",
          @"&(amp|#38);",
          @"&(lt|#60);",
          @"&(gt|#62);",
          @"&(nbsp|#160);",
          @"&(iexcl|#161);",
          @"&(cent|#162);",
          @"&(pound|#163);",
          @"&(copy|#169);",
          @"&#(/d+);",
          @"-->",
          @"<!--.*/n"
         };
            string[] aryRep = {
           "",
           "",
           "",
           "/"",
           "&",
           "<",
           ">",
           " ",
           "/xa1",//chr(161),
           "/xa2",//chr(162),
           "/xa3",//chr(163),
           "/xa9",//chr(169),
           "",
           "/r/n",
           ""
          };
            string newReg = aryReg[0];
            string strOutput = strHtml;
            for (int i = 0; i < aryReg.Length; i++)
            {
                Regex regex = new Regex(aryReg[i], RegexOptions.IgnoreCase);
                strOutput = regex.Replace(strOutput, aryRep[i]);
            }
            strOutput.Replace("<", "");
            strOutput.Replace(">", "");
            strOutput.Replace("/r/n", "");
            return strOutput;

        }
        //写一个静态方法

        #region 移除HTML标签

        /// <summary>
        /// 移除HTML标签
        /// </summary>
        /// <param name="HTMLStr">HTMLStr</param>
        public static string ParseTags(string HTMLStr)
        {

            return System.Text.RegularExpressions.Regex.Replace(HTMLStr, "<[^>]*>", "");

        }

 

        #endregion

        #region 取出文本中的图片地址

        /// <summary>
        /// 取出文本中的图片地址
        /// </summary>
        /// <param name="HTMLStr">HTMLStr</param>
        public static string GetImgUrl(string HTMLStr)
        {
            string str = string.Empty;
            string sPattern = @"^<img/s+[^>]*>";
            Regex r = new Regex(@"<img/s+[^>]*/s*src/s*=/s*([']?)(?<url>/S+)'?[^>]*>",
                RegexOptions.Compiled);
            Match m = r.Match(HTMLStr.ToLower());
            if (m.Success)
                str = m.Result("${url}");
            return str;
        }
        #endregion
    }