如何在子类用父类的魔术方法

class P{
    private $name="";
    function __construct(){
        $this->name="hello";
    }
    public function __set($name, $value){        
        $this->$name=$value;      
    }
    public function showName(){
        echo $this->name;
    }
}

class C extends P{
    function __construct(){
        parent::__construct();

        //想在这里给P类的$name换个值(你好)怎么做？
    }    
}

class P{
    private $name="";
    function __construct(){
        $this->name="hello";
    }
    public function __set($name, $value){        
        $this->$name=$value;      
    }
    public function showName(){
        echo $this->name;
    }
}
class C extends P{
    function __construct(){
        parent::__construct();
        $this->name = '你好';
    }    
}
$c=new C;
$c->showName();

print_r($c);

class P{
    private $name="";
    function __construct(){
        $this->name="hello";
    }
    public function __set($name, $value){
        $this->$name=$value;
    }
    public function showName(){
        echo $this->name;
    }
}


class C extends P{
    function __construct(){
        parent::__construct();
         //想在这里给P类的$name换个值(你好)怎么做？
		 $this->name = '你好';
    }
}

$obj = new C();
$obj->showName();