過濾函式

{
/// <summary>
/// 過濾標記
/// </summary>
/// <param name="NoHTML">包括HTML，指令碼，資料庫關鍵字，特殊字元的原始碼 </param>
/// <returns>已經去除標記後的文字</returns>
        public static string NoHTML(string str)
        {
string Htmlstring = str.ToLower();
if (Htmlstring == null)
            {
return "";
            }
else
            {
//刪除指令碼
                Htmlstring = Regex.Replace(Htmlstring, @"<script[^>]*?>.*?</script>", "", RegexOptions.IgnoreCase);
//刪除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, "xp_cmdshell", "", RegexOptions.IgnoreCase);

//刪除與資料庫相關的詞
                Htmlstring = Regex.Replace(Htmlstring, "select", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "insert", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "delete from", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "count''", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "drop table", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "truncate", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "asc", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "mid", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "char", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "xp_cmdshell", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "exec master", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "net localgroup administrators", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "and", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "net user", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "or", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "net", "", RegexOptions.IgnoreCase);
//Htmlstring = Regex.Replace(Htmlstring, "*", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "-", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "delete", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "drop", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "script", "", RegexOptions.IgnoreCase);
                Htmlstring = Regex.Replace(Htmlstring, "where", "", RegexOptions.IgnoreCase);

//特殊的字元
                Htmlstring = Htmlstring.Replace("<", "");
                Htmlstring = Htmlstring.Replace(">", "");
                Htmlstring = Htmlstring.Replace("*", "");
                Htmlstring = Htmlstring.Replace("-", "");
                Htmlstring = Htmlstring.Replace("?", "");
                Htmlstring = Htmlstring.Replace(",", "");
                Htmlstring = Htmlstring.Replace("/", "");
                Htmlstring = Htmlstring.Replace(";", "");
                Htmlstring = Htmlstring.Replace("*/", "");
                Htmlstring = Htmlstring.Replace("\r\n", "");
                Htmlstring = Htmlstring.Replace("\b", "");
                Htmlstring = Htmlstring.Replace("\f", "");
                Htmlstring = Htmlstring.Replace("\r", "");
                Htmlstring = Htmlstring.Replace("\n", "");
                Htmlstring = Htmlstring.Replace("\t", "");
                Htmlstring = Htmlstring.Replace("\'", "");
                Htmlstring = Htmlstring.Replace("\"", "");
                Htmlstring = Htmlstring.Replace("\\", "");
                Htmlstring = Htmlstring.Replace("=", "");
                Htmlstring = HttpContext.Current.Server.HtmlEncode(Htmlstring).Trim();

return Htmlstring;
            }
        }