<?php /** * 写一个父类一个子类,练习extends,public,private,protected的用法 */ header('content-type:text/html; charset=utf8'); class Fruit { public $name; protected $addr; private $quality; public function __construct($name='苹果',$addr='山西'){ $this->name = $name; $this->addr = $addr; } public function getAddr($addr='山西'){ return $this->name.'产地是'.$addr; } } class Bananer extends Fruit { public $color; public $weight; public function __construct($name='香蕉',$color='黄色的',$weight='5kg'){ parent::__construct($name); $this->color = $color; $this->weight = $weight; } public function getInfo(){ return $this->name.'是'.$this->color; } public function getWeight(){ return $this->name.'是'.$this->weight; } // public function getAddr(){ // return $this->addr; // } 不能再写这个 } echo '1.'.(new Fruit())->getAddr(); echo '<br>'; echo '2.'.(new Bananer())->getInfo(); echo '<br>'; echo '3.'.(new Fruit('橘子'))->getAddr('湖南'); echo '<br>'; echo '4.'.(new Bananer('香蕉','','100kg'))->getWeight(); echo '<br>'; echo '5.父类中的变量$addr'.(new Bananer())->getAddr(); echo '<br>';