How do I set and check a boolean variable in a for loop in a windows batch file? -

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i'm pretty new windows batch files i'm sure question has obvious answer i've been digging around online hours , haven't been able find it. when run following batch file, why doesn't output "it worked!"?

@echo off set /a _converted="0" set _converted if _converted==0 (echo worked!) else (echo didn't work)

output:

_converted=0 didn't work

but (i'm not sure how reproduce), outputs:

environment variable _converted not defined

here's i've tried:

  • set vs set /a
  • quotes in different places (set /a "_converted=0" vs. set /a _converted="0") "if use of logical or modulus operators, need enclose expression string in quotes."
  • my problem in loop can reproduce issue outside of loop don't think delayed variable expansion or this question helps me though looked similar.

put %'s around variable before checking value. use delayed expansion if in loop

as @aacini mentioned in comment, following prints "it worked!":

@echo off set /a _converted="0" set _converted if %_converted%==0 (echo worked!) else (echo didn't work)

the problem original issue within loop , messed if statement before moving simpler batch file try isolate problem. fix combine answer delayed variable expansion.


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