如何在PHP中打印stdClass对象的属性？

<?php
// 创建一个stdClass对象
$obj = new stdClass();
$obj->name = "张三";
$obj->age = 25;
$obj->gender = "男";

// 遍历stdClass对象的属性并打印
foreach ($obj as $key => $value) {
    echo $key . ": " . $value . "\n";
}
?>

name: 张三
age: 25
gender: 男

<?php
// 创建一个嵌套的stdClass对象
$obj = new stdClass();
$obj->name = "张三";
$obj->age = 25;
$obj->gender = "男";
$obj->address = new stdClass();
$obj->address->city = "北京";
$obj->address->district = "海淀区";
$obj->address->street = "中关村大街1号";

// 递归打印stdClass对象的属性
function printObject($obj, $prefix = "") {
    foreach ($obj as $key => $value) {
        if (is_object($value)) {
            printObject($value, $prefix . $key . ".");
        } else {
            echo $prefix . $key . ": " . $value . "\n";
        }
    }
}

printObject($obj);
?>

name: 张三
age: 25
gender: 男
address.city: 北京
address.district: 海淀区
address.street: 中关村大街1号