有人可以帮我解决这个增量/减量问题[重复]

Question

This question already has an answer here:

• What's the difference between ++$i and $i++ in PHP? 14 answers

I am new to php, for some reason the increment/decrement works inversely. Can someone tell me the reason behind this?

<?php

$var1 = 3;

echo "Addition = " . ($var1 += 3) . "<br>" ;
echo "Subtraction = " . ($var1 -= 3) . "<br>" ;
echo "Multiplication = " . ($var1 *= 3) . "<br>" ;
echo "Divison = " . ($var1 /= 3) . "<br>" ;
echo "Increment = " . $var1++ ;
echo "Decrement = " . $var1-- ;

?>

</div>

Answer 1

If you know how the increment and decrement operators work, you'll get the answer.

echo "Increment = " . $var1++ ; //Prints $var1 and then increments the value

echo "Decrement = " . $var1-- ; // Prints the incremented value from previous operation and then decrements the value

To achieve what you are trying to do, use --$var1