<?php
 //继承内容:PHP继承是子类继承父类所有的共有成员、受保护成员和私有属性,不能继承父类的私有方法
//封装
class saler{
    const ALLOW=true;
    private static $count=0;
    private $money=0;
    public function getMoney(){
        return $this->money;
    }
}

$s=new Saler();
$s->getMoney();//外部只能访问类中共有的方法,具体实现不可见。



//继承
    class father{
        private $dz;
        public function run($dz){
            $this->$dz=$dz;
            echo "我正在".$dz;
        }
    }
    class son extends father {

    }
    $xl=new son();
    $xl->run('跑');
?>

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class smartass{
    public $name;
    private $age;
    protected $sex;
    public function attend_class(){
        echo "我要上课了";
    }
    protected function class_dismissed(){
        echo "我要下课了";
    }
    private function Play_the_game(){
        echo "我要打游戏";
    }
}
class slacker extends smartass {
    function slacker_class_dismissed(){
        //继承的protected,子类只能在内部方法调用。
        $this->class_dismissed();
        $this->sex;
    }

}

$xlxz=new slacker();
$xlxz->$name='付哈哈';
$xlxz->attend_class();
echo "<br/>";
$xlxz->slacker_class_dismissed();

dRxJ0A.png

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1.PHP中继承只能单继承:即子类只有一个父类
2.PHP若想继承多个类,可以使用链式继承
3.PHP中继承只有私有方法不能被继承
4.PHP允许子类继承父类的构造方法和析构方法