PHP中是否有关键字引用祖父class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?
}

如何从 Kid class 中引用 Grandfather class 的成员？

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

Answer 1

如果 stuff() 在 class 层次结构中没有被覆盖，您可以使用 $this->stuff()
如果 stuff() 在 Dad 中被覆盖，您必须使用 class 名称调用该函数，例如Grandfather::stuff()
如果 stuff() 在 Kid 中被覆盖，您可以通过 parent::stuff()

Answer 2

如果你想调用 Grandfather::stuff 方法，你可以使用 Grandfather::stuff() in Kid class.

看看这个example。

Answer 3

$this->stuff() 要么 Grandfather::stuff()

调用此方法将调用继承级别顶部的 ::stuff() 方法（在你的例子中它会是 Dad::stuff()，但你不会在 Dad class 中覆盖 ::stuff 所以它会是 Grandfather::stuff()）

和Class::method()将调用精确的class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"会输出2次。因为 Dad 的构造函数（在 Kid class 中未被覆盖）class 调用 Grandfather::stuff() 而 Kid::doThatStuff() 也调用它

PHP中是否有关键字引用祖父class的成员？

Is there a keyword that refers to a member of a grandfather class in PHP?

php

oop