increment and decrement operators

PHP supports C-style pre- and post-increment and decrement operators.

Example Name Result
++$a Pre-increment Increments $a by one, then
returns $a.
$a++ Post-increment Returns $a, then increments $a by one.
–$a Pre-decrement Decrements $a by one, then
returns $a.
$a– Post-decrement Returns $a, then decrements $a by one.

Example :

<?php
echo "<h3>Postincrement</h3>";
$a = 5;
echo "Should be 5: " . $a++ . "<br />\n";
echo "Should be 6: " . $a . "<br />\n";

echo "<h3>Preincrement</h3>";
$a = 5;
echo "Should be 6: " . ++$a . "<br />\n";
echo "Should be 6: " . $a . "<br />\n";

echo "<h3>Postdecrement</h3>";
$a = 5;
echo "Should be 5: " . $a-- . "<br />\n";
echo "Should be 4: " . $a . "<br />\n";

echo "<h3>Predecrement</h3>";
$a = 5;
echo "Should be 4: " . --$a . "<br />\n";
echo "Should be 4: " . $a . "<br />\n";
?>