Master the correct posture for sorting arrays in PHP

Arrays are a more commonly used data type in PHP. How to sort the data in the array to facilitate data management. This article will take you to see how to sort the array using PHP's built-in functions.

1. Sort the array according to the array key value

<?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);
?>

输出：Array ( [0] => 0 [1] => 1 [2] => 2 [3] => 3 [4] => 5 )
      Array ( [0] => 5 [1] => 3 [2] => 2 [3] => 1 [4] => 0 )

sort() - Sort the array Sort in ascending order; rsort() - Sort the array in descending order

2. Sort the array according to the associative array key value

<?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";
}
?>

输出：a = orange;d = lemon;b = banana;c = apple;
      c = apple b = banana d = lemon a = orange

arsort() - Sort the array in descending order according to the value of the associative array; asort() - Sort the array in ascending order according to the value of the associative array

3. Sort the array according to the key of the associative array

<?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";
}
?>

输出：d = lemon c = apple b = banana a = orange
      a = orange b = banana c = apple d = lemon

krsort() - Sort the array according to the key of the associative array Sort in descending order;ksort() - Sort the array in ascending order according to the key of the associated array

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