<?php 
        class Vehicle{
            protected $brand;

            function __construct($brand){
                $this->setBrand($brand);
            }
            function setBrand($brand){
                $this->brand=$brand;
            }

            function getBrand(){
                return $this->brand;
            }

            function honk(){
                echo "Beep Beep Beep...";
            }
        }

        class Car extends Vehicle{
            private $modelName;

            function setModelName($modelName){
                $this->modelName=$modelName;
            }

            function getModelName(){
                return $this->modelName;
            }
        }

        $carObject = new Car("Lamborghini");
        echo "</br>Car brand is ".$carObject->getBrand()."<br>";
        $carObject->setModelName("Aventador");
        echo "Car model is ".$carObject->getModelName()."<br>";

        echo($carObject->getBrand()." ".$carObject->getModelName()." is ".$carObject->honk());

    ?>

字符串
我把这个函数添加到子类中。但是我也不理解那个函数。

function honk(){
    parent::honk();
}

型
我想要的输出是：兰博基尼Aventador是哔......但我得到哔......兰博基尼Aventador是