Combine multiple lines from one text file into one line

Question

So I have a file with multiple lines of letters and numbers as shown:

a 
1
h
7
G
k
3
l

END

I need a type of code that combines them together and preferably outputs it into a variable as shown:

var=a1h7Gk2l

Any help would be appreciated.

Answer 1

@echo off
setlocal enableDelayedExpansion
set "var="
for /f "usebackq" %%A in ("test.txt") do set var=!var!%%A
echo !var!

Edit
I assumed "END" does not physically exist in your file. If it does exist, then you can add the following line after the FOR statement to strip off the last 3 characters.

set "!var!=!var:~0,-3!"