Did you know that you can do basic arithmetic operations in a Batch file script?
The syntax is simple:
set /A result=EXPR
For example, to add 10 and 20:
@echo off set /p result=10+20 echo result=%result%
From the “SET /?” output, these are the supported arithmetic operations:
The /A switch specifies that the string to the right of the equal sign
is a numerical expression that is evaluated. The expression evaluator
is pretty simple and supports the following operations, in decreasing
order of precedence:
() - grouping
! ~ - - unary operators
* / % - arithmetic operators
+ - - arithmetic operators
<< >> - logical shift
& - bitwise and
^ - bitwise exclusive or
| - bitwise or
= *= /= %= += -= - assignment
&= ^= |= <<= >>=
, - expression separator
Now, let’s make a simple interactive calculator:
@echo off :main setlocal set /p num1=Enter first number: set /p op=Enter operator: set /p num2=Enter second number: set /a result=%num1% %op% %num2% echo Result is %result% endlocal goto :eof
When we enter: 4, * then 5, we get the following output:
Enter first number:4 Enter operator:* Enter second number:5 Result is 20
The Batchography book covers this topic in details and more. Check it out!
You might also like: