Sorting Arrays in PHP: Using sort(), rsort(), asort(), arsort(), ksort() and krsort()

PHP arrays are commonly used, and sorting them helps data management. This article demonstrates how to sort arrays using built‑in PHP functions.

1. Sorting indexed arrays by values

<?php
$arr1 = array(3,1,5,2,0);
sort($arr1);
print_r($arr1);
echo "<br>";
$arr2 = array(3,1,5,2,0);
rsort($arr2);
print_r($arr2);
?>

sort() arranges the array in ascending order, while rsort() arranges it in descending order.

2. Sorting associative arrays by values

<?php
$fruits1 = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");
arsort($fruits1);
foreach ($fruits1 as $key => $val) {
    echo "$key = $val;";
}
echo "<br>";
$fruits2 = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");
asort($fruits2);
foreach ($fruits2 as $key => $val) {
    echo "$key = $val\n";
}
?>

arsort() sorts an associative array by its values in descending order, whereas asort() sorts them in ascending order.

3. Sorting associative arrays by keys

<?php
$fruits1 = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");
krsort($fruits1);
foreach ($fruits1 as $key => $val) {
    echo "$key = $val\n";
}
echo "<br>";
$fruits2 = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");
ksort($fruits2);
foreach ($fruits2 as $key => $val) {
    echo "$key = $val\n";
}
?>

krsort() sorts an associative array by its keys in descending order, while ksort() sorts them in ascending order.