batch file - Set output of a command as a variable (with pipes)

Question

Can you redirect the output of a command to a variable with pipes?

I haven't tried much as I haven't been able to think of anything to try, but I have tried one method (with two variations)...

For example:

echo Hello|set text=

Didn't work, neither did:

echo Hello | set text=

I know you can do it fairly easily with the FOR command, but I think it would look "nicer" with a pipe.

And if you're wondering, I don't have a specific reason I'm asking this other than I'm curious and I can't find the answer.

Answer 1

Your way can't work for two reasons.

You need to use set /p text= for setting the variable with user input.
The other problem is the pipe.
A pipe starts two asynchronous cmd.exe instances and after finishing the job both instances are closed.

That's the cause why it seems that the variables are not set, but a small example shows that they are set but the result is lost later.

set myVar=origin
echo Hello | (set /p myVar= & set myVar)
set myVar

Outputs

Hello
origin

Alternatives: You can use the FOR loop to get values into variables or also temp files.

for /f "delims=" %%A in ('echo hello') do set "var=%%A"
echo %var%

or

>output.tmp echo Hello
>>output.tmp echo world

<output.tmp (
  set /p line1=
  set /p line2=
)
echo %line1%
echo %line2%

Alternative with a macro:

You can use a batch macro, this is a bit like the bash equivalent

@echo off

REM *** Get version string 
%$set% versionString="ver"
echo The version is %versionString[0]%

REM *** Get all drive letters
`%$set% driveLetters="wmic logicaldisk get name /value | findstr "Name""
call :ShowVariable driveLetters

The definition of the macro can be found at
SO:Assign output of a program to a variable using a MS batch file