提取HTML代码中文字的C#函数

/// <summary>
  /// 去除html标记
  /// </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*(([""'])(file://[""'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;
  }