检测字符串中是否有非法的字符，如果有，返回true

 /// <summary>
        /// 检测字符串中是否有非法的字符，如果有，返回true
        /// </summary>
        /// <param name="badword">要检查的字符串</param>
        /// <returns></returns>
        public static bool ChkBadWord(string badword)
        {
            string[] bw = strbadword();
            bool isok = false;
            foreach (string str in bw)
            {
                if (badword.IndexOf(str) > -1)
                {
                    isok = true;
                    return isok;
                }

            }
            return isok;
        }
        private static string[] strbadword()
        {
            string[] bad = new string[16];
            bad[0] = "'";
            bad[1] = "\"";
            bad[2] = ";";
            bad[3] = "--";
            bad[4] = ",";
            bad[5] = "!";
            bad[6] = "@";
            bad[7] = "#";
            bad[8] = "$";
            bad[9] = "%";
            bad[10] = "^";
            bad[11] = "&";
            bad[12] = "*";
            bad[13] = "-";
            bad[14] = "+";
            bad[15] = "~";
            return bad;
        }