>Can be optimized in that case
>
>would be like this
>

>public static string ChrTran(this string s, string[]  from, string[] to)
>

>
>Of course - the length of the arrays from and to must be equal
>
>It's an extra loop. sb needs to be instantiated only once, and only once sb.ToString();
>
>
>Also, in the oiginal code above from and to are not checked for null values

Here is the code I have in VFP

 lcInvalidChars   = chr(0) + chr(1) + chr(2) + chr(3) + chr(4) + chr(5) + chr(6) + chr(7) + chr(11) + ;
                               chr(12) + chr(14) + chr(15) + chr(16) + chr(17) + chr(18) + chr(19) + chr(20) + chr(21) + chr(22) + ;
                               chr(23) + chr(24) + chr(25) + chr(26) + chr(27) + chr(28) + chr(29) + chr(30) + chr(31)
            tvFieldValue   = chrtran(tvFieldValue, lcInvalidChars, ' ')

And this is what I just added to our functions using your code in this thread:

/// <summary>
        /// ChrTran
        /// <B>Re: Chrtran in .NET</B> Thread #1360482 Message #1360903
        /// </summary>
        /// <param name="s"></param>
        /// <param name="from"></param>
        /// <param name="to"></param>
        /// <returns></returns>
        public static string ChrTran(this string s, string from, string to)
        {
            // check parameters
            if (String.IsNullOrEmpty(s))
                return s;

            if (String.IsNullOrEmpty(from))
                return s;


            // (1) Split from into translate and remove

            // "1234", "56"
            // translate = "12"
            // remove = "34"
            char[] translate, remove;

            // "1234", ""
            if (String.IsNullOrEmpty(to))
            {
                translate = new char[0];

            }
            // "1234", "5678"
            // "1234", "56"
            // "1234", "A"
            // "1234", "567890"  - can happen
            else
            {
                translate = new char[Math.Min(from.Length, to.Length)];
                from.CopyTo(0, translate, 0, translate.Length);
            }

            remove = new char[from.Length - translate.Length];
            from.CopyTo(translate.Length, remove, 0, remove.Length);

            // (2) remove chars from s - but not those that will be translated
            //	avoid	StrTran("AA", "B")
            //			translate = "A", to = "B"
            //			remove = "A"
            var sb = new StringBuilder(s, s.Length);
            int i, j;

            for (i = remove.Length; --i >= 0; )
            {
                if (!translate.Contains(remove[i]))
                    sb.Replace(remove[i].ToString(), null);
            }

            // (3) translate

            // if no char in from is in to, then a fast translate can be done
            //  if not, we'll have to loop

            if (translate.Length > 0)
            {
                bool fastTranslate = true;

                for (i = translate.Length; --i >= 0; )
                {
                    if (to.Contains(from[i]))
                    {
                        fastTranslate = false;
                        break;
                    }
                }

                if (fastTranslate)
                {
                    for (i = translate.Length; --i >= 0; )
                    {
                        sb.Replace(translate[i], to[i]);
                    }
                }
                else
                {
                    for (i = sb.Length; --i >= 0; )
                    {
                        if ((j = Array.IndexOf<char>(translate, sb[i])) >= 0)
                            sb[i] = to[j];
                    }
                }
            }
            return sb.ToString();
        }

So, assuming this is correct, how would I call it for the above case?

Thanks again.