掌握PHP中对数组进行排序的正确姿势

PHP中数组是较为常用的数据类型，如何对数组中的数据进行排序，以方便对数据进行管理，本文就带大家一起来看一看如何利用PHP内置函数对数组进行排序。

1.依据数组键值对数组排序

<?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() – 对数组进行升序排列； rsort() – 对数组进行降序排列

2.依据关联数组键值对数组排序

<?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
";
}
?>

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

arsort() – 根据关联数组的值，对数组进行降序排列；asort() – 根据关联数组的值，对数组进行升序排列

3. 根据关联数组的键对数组排序

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

$fruits2 = array("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");
ksort($fruits2);
foreach ($fruits2 as $key => $val) {
    echo "$key = $val
";
}
?>

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

krsort() – 根据关联数组的键，对数组进行降序排列；ksort() – 根据关联数组的键，对数组进行升序排列

推荐：《2021年PHP面试题大汇总（收藏）》《php视频教程》