SETLOCAL enabledelayedexpansion
call:Randomize rnd 100 200
echo !rnd!
 
:Randomize
SETLOCAL enabledelayedexpansion
IF "%~2"=="" GOTO:EOF
SET /a "r=%RANDOM% %% %~3 + %~2" > NUL
( ENDLOCAL
    set "%~1=%r%"
)
GOTO:EOF

TAGS : Tutorial DOS function Randomize SETLOCAL SET enabledelayedexpansion