php - PHP 中是否有一个关键字引用祖父类的成员？

Question

class Grandfather {

    protected function stuff() {
        // Code.
    } 
}

class Dad extends Grandfather {
    function __construct() {
        // I can refer to a member in the parent class easily.
        parent::stuff();
    }
}

class Kid extends Dad {
        // How do I refer to the stuff() method which is inside the Grandfather class from here?
}

我如何从 Kid 类中引用 Grandfather 类的成员？

我的第一个想法是Classname::method()，但是是否有可用的关键字，例如self或parent？

Answer 1

$this->stuff()或者祖父::stuff()

调用此方法将调用继承级别顶部的 ::stuff() 方法(在您的示例中，它是 Dad::stuff()，但您不会覆盖 Dad 类中的 ::stuff ，因此它是Grandfather::stuff())

和Class::method()将调用确切的类方法

示例代码:

    <?php
class Grandfather {

    protected function stuff() {
        echo "Yeeeh";
        // Code.
    } 
}

class Dad extends Grandfather {
    function __construct() {
        // I can refer to a member in the parent class easily.
        parent::stuff();
    }
}

class Kid extends Dad {
    public function doThatStuff(){
        Grandfather::stuff();
    }
      // How do I refer to the stuff() method which is inside the Grandfather class from here?
}
$Kid = new Kid();
$Kid->doThatStuff();

“Yeeeh”将输出2次。因为 Dad 的构造函数(在 Kid 类中未重写)类调用 Grandfather::stuff() 和 Kid::doThatStuff () 也调用它