|AFAIK you cannot test each digit as it is typed. However, after the digits have been <Entered> you can test the variable to ensure it contains only numeric digits. Amend the following untested script to suit your needs:|
set /p var=Enter numerics:
FOR /F "tokens=1 delims=%chars%" %%1 IN ("%var%") do (
ECHO %Var% contains at least one Non-Numeric character.
Did you Google for an answer before asking the question?