phpwind 无限分类的展示

<?php
// 数据库连接
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "phpwind";

$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 获取所有分类
$sql = "SELECT id, name, parent_id FROM categories";
$result = $conn->query($sql);

$cats = [];
while ($row = $result->fetch_assoc()) {
    $cats[$row['id']] = $row;
}

// 递归函数生成分类树
function buildTree(array &$elements, $parentId = 0) {
    $branch = [];

    foreach ($elements as $element) {
        if ($element['parent_id'] == $parentId) {
            $children = buildTree($elements, $element['id']);
            if ($children) {
                $element['children'] = $children;
            }
            $branch[] = $element;
        }
    }

    return $branch;
}

$tree = buildTree($cats);

// 输出分类树
function printTree($tree, $level = 0) {
    foreach ($tree as $item) {
        echo str_repeat("  ", $level) . $item['name'] . "\n";
        if (isset($item['children'])) {
            printTree($item['children'], $level + 1);
        }
    }
}

printTree($tree);

$conn->close();
?>