using System.Text.RegularExpressions;

​

        public static string ReplaceSymbols(string txt)

        {

            string r = "[\x00-\x08\x0B\x0C\x0E-\x1F\x26]";

            txt = Regex.Replace(txt, r, " ", RegexOptions.Compiled);

            txt = txt.Replace("<", "&lt;");

            txt = txt.Replace(">", ">");

            txt = txt.Replace("\n\n", "**SALTO**");

            txt = txt.Replace("\n", "");

            txt = txt.Replace("**SALTO**", "\n\n");            

​

            return txt;

        }