数组

<?php
// 索引数组
$fruits = ["苹果", "香蕉", "橙子"];
echo $fruits[0];             // 苹果
array_push($fruits, "葡萄");
echo "<br>" . count($fruits);   // 4

// 关联数组
$user = [
    "name" => "小王",
    "age" => 25,
    "city" => "烟台"
];
echo "<br>" . $user["name"];

// 多维数组
$students = [
    ["name" => "小王", "score" => 92],
    ["name" => "小李", "score" => 88]
];
echo "<br>" . $students[0]["name"] . "：" . $students[0]["score"];

// 常用函数
$nums = [3, 1, 4, 1, 5];
sort($nums);                 // 升序排序
echo "<br>" . implode(",", $nums);   // 1,1,3,4,5

$even = array_filter($nums, fn($n) => $n % 2 == 0);
echo "<br>偶数：" . implode(",", $even);   // 4

// 遍历
foreach ($user as $k => $v) {
    echo "<br>$k = $v";
}
?>