How can I put the entire Powershell output into a Batch variable?
Another post has suggested
@for /f "delims=" %%a in ('Powershell -C Get-Content myFile.txt -Raw') do Set "myVar=%%a"
but that only returns the last line.
My end goal is to read a multi-line text file and pass it into another script.
[EDIT] Conclusion: batch is not made for this as variables cannot contain a newline character without obscure tricks, I'm switching to Powershell.
An attempt to provide the bigger picture:
It is possible to store multiline string values in batch-file variables - and therefore also to read a file's content into a variable with for /f - but the technique for doing so is obscure, cumbersome, and limited to ca. 8,190 characters, excluding an optional trailing newline[1] - see jeb's helpful answer, which builds on an of necessity Byzantine, but robust[2] solution introduced in an earlier answer of his.
Therefore, it's best to pass file content to a target script or utility either indirectly, by a file path argument or via stdin (e.g. < myFile.txt or type myFile.txt | ...); of course, the target script or utility must be designed to accept file content this way.
If feasible, switch to PowerShell altogether, whose scripting language is far superior to that of batch files. Notably, in the case at hand the solution would be as simple as:
$myVar = Get-Content myFile.txt -Raw
[1] The exact limit depends on whether the the file contains a single line only (optionally followed by a trailing newline) or multiple lines: in the single-line case, the limit is 8,144 vs. 8,190 in the multiline case.
[2] There is one edge case that isn't covered: If the input file's last (or only) line contains only a single character and isn't followed by a newline.
Fundamentally, a batch variable can only contain a single string, so you need to put your data into many variables. There are many ways to do this, documented on SO through thousands of examples.
To devise a way to suit you, we would need to know more about the data that your powersmell application produces.
Two common ways are
FOR /f "tokens=1* delims=:" %b IN ('somecommandwithtextoutput^|findstr /n /R ".*" ""') DO SET "$%b$=%c"&SET /a $0=%b
FOR /f "tokens=1* delims=][" %b IN ('somecommandwithtextoutput^|find /v /n ""') DO SET "$%b$=%c"&SET /a $0=%b
These exploit the delimiters capabilities of for /f by finding and parsing the strings produced. The ^| is an escaped-pipe to deliver the text to the find utility chosen. The first uses /n to prefix the lines found with number: the second with [number]. the set thus produces environment variables named $1=first line $2=second line, etc and $0=line count
The choice of $ is arbitrary - it can be any valid variablename.
set $
can be used to display the variables set.
Processing beyon that is another issue completely, and will also involve understanding of the effects of "Poison characters" (those with special meaning to the batch language, such as !%~&^())
myFile.txt itself or even call the succeeding script and have it reconstruct the file from the inherited environment?A batch variable can contain new line characters, but to use it for a search & replace operation is a complex task.
Another limiting factor is that a variable can contain a maximum of 8,191 characters.
Reading a file/command output into a variable can be solved with SO: Assign output of a program to a variable using a MS batch file
@echo off
setlocal
call :initMacro
setlocal EnableDelayedExpansion
%$set% myVar="type myFile.txt"
echo fileContent: !myVar!
exit /b
But this will not solve the complex task of using this for search and replace.
