Why this code says echo is off?

Question

What is wrong with this code? It says ECHO is off.

@ECHO off
set /p pattern=Enter id:
findstr %pattern% .\\a.txt > result
if %errorlevel%==0 (
se         


        

Answer 1

As Laurent stated, it's not a problem of the ECHO, it's a problem of your code.

In batch files, blocks are completely parsed before they are executed.
While parsing, all percent expansion will be done, so it seems that your variables can't be changed inside a block.

But for this exists the delayed expansion, the delayed expansion will be evaluated in the moment of execution not while parsing the block.

It must be enabled, as per default the delayed expansion is disabled.

@ECHO off
setlocal EnableDelayedExpansion
set /p pattern=Enter id:
findstr %pattern% .\a.txt > result
if %errorlevel%==0 (
  set var2=  test.txt
  echo(!var1!
) else (
  echo error
)
del result

I used here the construct echo( instead of echo as this will ensure echoing an empty line even if the variable is empty.