Allowing multiple choice selections for users using batch file [duplicate]

Answer 1

You wrote, you tried ('%op'), ("%op"), (%op) and variations.

It should be: ("%op%")

Only forvariables and Commandline-Parameters use <Percent><char> syntax.

op is a "normal" variable and it is used <Percent><name><Percent>: %op%

Answer 2

You may make good use of the fact that the standard separators for items in flat FOR command (no /F option) are spaces, commas, semicolons and equal-signs:

@echo off
setlocal enabledelayedexpansion

echo Which would you like to use?

echo 1. Hello.txt
echo 2. Byebye.txt
echo 3. ThisIsText.txt
echo 4. MyBatchScript.txt
echo 5. All

:getOptions
set /p "op=Type the numbers of the names you want to use (separated by commas OR spaces): "
if "%op%" equ "" goto getOptions

if %op% equ 5 set op=1,2,3,4
for %%a in (%op%) do (
   echo Process option %%a
   call :option-%%a
)
goto :EOF

:option-1
echo 1. Hello.txt
exit /B

:option-2
echo 2. Byebye.txt
exit /B

:option-3
echo 3. ThisIsText.txt
exit /B

:option-4
echo 4. MyBatchScript.txt
exit /B