PHP 类的继承 实例讲解

<?php
    class Vegetables{   //父类
        var $tomato = "西红柿";    //父类属性
        var $cucumber = "黄瓜";
    }
    class Vegetables_type extends Vegetables{   //类之间的继承，子类继承了父类的属性
        var $potato = "土豆";  //子类独有的属性
        var $radish = "萝卜";
    }
    $vegetable = new Vegetables_type(); //实例化子类
    echo "蔬菜包括：".$vegetable->tomato."、".$vegetable->cucumber."、".$vegetable->potato."、".$vegetable->radish;
    /* 运行结果：
         蔬菜包括：西红柿、黄瓜、土豆、萝卜
    */