PHP 高级课程笔记 面向对象

例一：

<?php 
// 类的定义 
class User 
{ 
// 属性,注意public、private、protected的作用范围 
public $name = "hackbaby"; 
// 构造函数 
function __construct() 
{ 
echo "construct<br />"; 
} 
// 方法 
function say() 
{ 
echo "这是在类的本身调用：$this->name"; 
} 
// 析构函数 
function __destruct() 
{ 
echo "destruct"; 
} 
// 返回当前对象的描述信息 通过实例化的变量名调用例如本例中的$user 
function __toString() 
{ 
return "user class"; 
} 
} 
//实例化，如果构造函数有参数则用$user = new User('参数'); 
$user = new User(); 
echo $user->name . "<hr />"; 
$user->say(); 
echo "<hr />"; 
echo $user; 
?>

例二：

<?php 
class Fruit 
{ 
protected $fruit_color; 
protected $fruit_size; function setcolor($color) 
{ 
$this->fruit_color = $color; 
} 
function getcolor() 
{ 
return $this->fruit_color; 
} 
function setsize($size) 
{ 
$this->fruit_size = $size; 
} 
function getsize() 
{ 
return $this->fruit_size; 
} 
function save() 
{ 
//代码 
} 
} 
class apple extends Fruit 
{ 
private $variety; 
function setvariety($type) 
{ 
$this->variety = $type; 
} 
function getvariety() 
{ 
return $this->variety; 
} 
} 
$apple = new apple(); 
echo $apple->setvariety('红富士'); 
echo $apple->getvariety(); 
echo "<br />"; 
echo $apple->setcolor('red'); 
echo $apple->getcolor(); 
echo "<br />"; 
echo $apple->setsize('特大'); 
echo $apple->getsize(); 
?>