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\n;
}
?>

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\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() - 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

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