PHP之OOP——foreach

<?php
    
    //对象的遍历，所用的对象都存储在 php内部的一个 叫 stdclass 类的集合中
    header("content-Type:text/html;charset=utf-8");
class Student{
    public $name;
    public $gender;
    private $_age;

    //声明构造方法
    public function __construct($name, $gender, $_age){
        $this->name = $name;
        $this->gender = $gender;
        $this->$_age = $_age;
    }

}

$s  = new Student('徐进','male','20');

// var_dump($s);
foreach ($s as $key => $value) {
    var_dump($key,$value);
}

echo "<hr>";
//把对象强制转换城数组

$arr = array('name'=>'xujin','age'=>'20','gender'=>'male');
$arr1 = (object) $arr;
foreach ($$arr1 as $key => $value) {

    var_dump($key,$value);
}