php 筛选

<?php
$array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

// 筛选出偶数
$evenNumbers = array_filter($array, function($value) {
    return $value % 2 == 0;
});

print_r($evenNumbers);
?>

Array
(
    [1] => 2
    [3] => 4
    [5] => 6
    [7] => 8
    [9] => 10
)

<?php
$array = ['apple', 'banana', 'cherry'];

// 将所有水果名称转换为大写
$upperCaseFruits = array_map('strtoupper', $array);

print_r($upperCaseFruits);
?>

Array
(
    [0] => APPLE
    [1] => BANANA
    [2] => CHERRY
)

<?php
$array = [1, 2, 3, 4, 5];

// 计算数组元素的总和
$sum = array_reduce($array, function($carry, $value) {
    return $carry + $value;
}, 0);

echo $sum; // 输出 15
?>

<?php
$array = [1, 2, '3', 4, 5];

// 筛选出数字类型的元素
$numbers = array_filter($array, function($value) {
    return is_numeric($value);
});

print_r($numbers);
?>

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