在PHP中查找JSON中键的路径

<?php
function findKeyPath($json, $key, $path = '') {
    foreach ($json as $k => $v) {
        if ($k === $key) {
            $path .= '/' . $k;
            return $path;
        }
        if (is_array($v) || is_object($v)) {
            $result = findKeyPath($v, $key, $path . '/' . $k);
            if ($result !== false) {
                return $result;
            }
        }
    }
    return false;
}

$jsonData = '{
    "name": "John",
    "age": 30,
    "address": {
        "street": "123 Main St",
        "city": "New York"
    },
    "pets": [
        {
            "name": "Max",
            "type": "dog"
        },
        {
            "name": "Lucy",
            "type": "cat"
        }
    ]
}';

$json = json_decode($jsonData, true);
$key = 'city';
$path = findKeyPath($json, $key);

if ($path !== false) {
    echo "The path of '{$key}' is: {$path}";
} else {
    echo "The key '{$key}' was not found in the JSON.";
}
?>