How to Increment / Decrement a Number with PHP

Incrementing and decrementing a variable can be accomplished with C-style pre- and post-operators. The pre-operators return the value after it as been incremented or decremented, post- return the value before. Let’s take a look at incrementing first:

$i = 1
echo ++$i // outputs 2
echo $i++ // also outputs 2
echo $i   // outputs 3

You can pick either the pre- or post-operator based on whether you want to interact with the value of the variable before or after it’s been operated on. To decrement, just swap the ++ for --:

$i = 10
echo --$i // outputs 9
echo $i-- // also outputs 9
echo $i   // outputs 8

In a future post I’ll be discussing incrementing and decrementing by a value other than 1 and also applying the same logic to a string O_o

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