Question

i try to add two numbers received from a file.
But it shows only the last value of sum. Thx for the help!

@FOR /F "eol=; tokens=1-3 delims=, " %%i IN (test.txt) DO (  
   set m=%%j   
   set n=%%k  
   set /a sum=%m%+%n%  
   echo sum = %sum%  
   )  

and in the test.txt i have

alex 4 5  
john 6 7  

and i want to see

sum=9  
sum=13  

it only shows

sum=13  
sum=13

Answer 1

The problem is the percent expanding in the line set /a sum=%m%+%n% and echo sum = %sum%.
These are expanded before the FOR-loop is executed.

Therefore you got the result of the “global” set of sum.

It’s better to use the delayed expansion, as then all variables enclosed with ! are expanded at runtime not parsetime

@echo off
setlocal EnableDelayedExpansion
FOR /F "eol=; tokens=1-3 delims=, " %%i IN (test.txt) DO (  
   set m=%%j   
   set n=%%k  
   set /a sum=m+n
   echo sum = !sum!
)