class类属性变量和类方法函数

<?php

class Animal {
    public string $name = "小黑";
    public int $age = 1;
    public function eat(): void
    {
        echo $this->name . "在吃饭";
    }
    public function say(): void
    {
        // $this 代表自身的对象
        echo $this->name ."在说话";
    }

}
$cat = new Animal;
$cat->name = "小红";
echo $cat->eat();

$dog = new Animal;
echo $dog->say();