asp.net过滤HTML标签的几个函数

 

using System.Text.RegularExpressions;
using System.Web;

namespace Tools
{
    public class FiterHtml
    {
        ///   <summary>
        ///   去除HTML标记
        ///   </summary>
        public static string NoHTML(string Htmlstring)
        {
            //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.Replace("<", "");
            Htmlstring.Replace(">", "");
            Htmlstring.Replace("/r/n", "");
            Htmlstring = HttpContext.Current.Server.HtmlEncode(Htmlstring).Trim();

            return Htmlstring;
        }
        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;
        }
        ///   <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, "<[^>]*>", "");
        }
        ///   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;
        }

    }
}