Question

I’m trying to get substrings of file names in a current folder. Later I’m going to pass these as arguments to a certain command but as for now I can’t even make echo to work:

setlocal EnableDelayedExpansion

for %%f in (*.mvx) do (
  set a=%%f
  echo %a%
  echo %%a%%
  echo %a:~3,8%
)
endlocal
pause

yields results of the kind:

C:\1>(
set a=xx-20121213-mvl-0005.mvx
 echo
 echo %a%
 echo ~3,8
)
ECHO is on.
%a%
~3,8

the last one is supposed to return “20121213” for the case.

Answer 1

You need to use delayed expansion to echo your variables, as you have set them in a for loop.

You have already included the line to enable it, you just need to turn your %‘s into !‘s

setlocal EnableDelayedExpansion

for %%f in (*.mvx) do (
  set a=%%f
  echo !a!
  echo !a:~3,8!
)
endlocal
pause

Update

To put the entire script on a one line cmd command you can use

cmd /v:on /c "for %f in (*.mvx) do set a=%f && echo !a! && echo !a:~3,8! && pause"