String is Not Numeric - crystal-reports

Question

Having an issue when attempting to run a Mod formula against a field. I keep receiving the error "String is Not Numeric" and so far I have not been able to get ToNumber to correctly format the field. The field is being generated by adding a static value and three fields that have been padded. Any help would be appreciated.
Combines fields and pads
StringVar strMICR;
StringVar strMICRLINE;
strMICRLINE := Chr(13) & "0603250694";
strMICRLINE := strMICRLINE & Right("000000" & Trim(Split({CUST.C_ID_ALPHA},"-")[1]),6);
strMICRLINE := strMICRLINE & Right("00000000" & ToText({STMT.STMT_NUMBER},0,""),8);
strMICRLINE := strMICRLINE & Right("0000000000" & Replace(ToText({#Total},2,""),".",""),10);
//Uncomment below to test Mod10 Check-digit
//strMICR := mod10("0603250694084469108961440000127874");
//IF NumericText (strMICRLINE)
//THEN ToNumber (strMICRLINE);
Mod10 (strMICRLINE);
MOD10 Function
Function (StringVar input_number)
input_number := replace(input_number, " ", "");
numbervar i := length(input_number);
numbervar sum_val := 0;
stringvar position := "odd";
do (
if position = "odd" then (
sum_val := sum_val + 3*tonumber(input_number[i]);
position := "even" )
else (
sum_val := sum_val + tonumber(input_number[i]);
position := "odd" )
;
i := i-1
) while i > 0;
numbervar remainder_val := Remainder(sum_val, 10);
numbervar check_digit := if remainder_val = 0 then 0 else (10-remainder_val) ;
input_number + ToText(check_digit, 0)

Answer 1

You're attempting to call toNumber() on a string that is not numeric and therefore can't be converted. You need to strip all non-numeric characters out of your string first.
//Formula sample to strip non-numeric characters
local stringvar input := "78906-adf0asdf-234";
local stringvar output;
local numbervar i;
for i:=1 to length(input) do
if numerictext(input[i]) then output:=output&input[i];
output
Then I would highly suggest you use the built in mod function instead of rolling your own.
toNumber({#NumericTextOnly}) mod 10