ASP.NET去掉HTML标记

using System;
using System.Web;
using System.Text.RegularExpressions;
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   = &nbs