Batch File input validation - Make sure user entered an integer

Question

I\'m experimenting with a Windows batch file to perform a simple operation which requires the user to enter a non-negative integer. I\'m using simple batch-file techniques t

Answer 1

Thanks all. I was trying to make it harder for myself looking at loops and string manipulation. I used your tips on math evaluation and comparison. Here's what I finally came up with as my concept script:

:Top
@ECHO OFF
ECHO.
ECHO ---------------------------------------
SET /P UserInput=Please Enter a Number: 
ECHO.
ECHO UserInput = %UserInput%
ECHO.
SET /A Evaluated=UserInput
ECHO Math-Evaluated UserInput = %Evaluated%
if %Evaluated% EQU %UserInput% (
    ECHO Integer
    IF %UserInput% GTR 0 ( ECHO Positive )
    IF %UserInput% LSS 0 ( ECHO Negative )
    IF %UserInput% EQU 0 ( ECHO Zero )
    REM - Other Comparison operators for numbers
    REM - LEQ - Less Than or Equal To
    REM - GEQ - Greater Than or Equal To
    REM - NEQ - Not Equal To
) ELSE (
    REM - Non-numbers and decimal numbers get kicked out here
    ECHO Non-Integer
)

GOTO Top

This method catches all numbers and can detect whether it's positive, negative, or zero. Any decimal or string will be detected as non-integers. The only edge case I've found is a string with spaces. For example, the text "Number 1" will cause the script to crash/close when the user input is evaluated as math. But in my situation, this is fine. I don't want my script to go on with invalid input.