字符串过滤

这个我这里自己一直用的几个函数，下面贴出来。
       希望尽量不是直接要实例就去用，而不关心他本来的意义和实现思路等。加油！

using System;
using System.Collections.Generic;
using System.Text;
using System.Text.RegularExpressions;

            ///

            /// 对字符串进行检查和替换其中的特殊字符
            ///

            ///
            ///
            public static string HtmlToTxt(string strHtml)
            {
                string[] aryReg ={
                        @"]*?>.*?",
                        @"<(///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+);",
                        @"-->",
                        @"