PHP5面向对象开发教程第二章-PHP5面向对象进阶

2.1 类的继承..........................................................................................................................3
什么是继承.......................................................................................................................3
PHP5中的继承................................................................................................................5
继承的简单例子...............................................................................................................6
构造函数的继承...............................................................................................................8
私有变量和方法不被继承...............................................................................................9
2.2访问控制...........................................................................................................................10
Private的访问权限.........................................................................................................10
protected的访问权限......................................................................................................11
public的访问权限...........................................................................................................12
2.3 重写（override）..........................................................................................................13
重写方法与访问权限.....................................................................................................15
重写时的参数数量.........................................................................................................16
构造函数重写.................................................................................................................17
2.4 this关键字......................................................................................................................18
局部变量和全局变量与 $this 关键字.........................................................................19
用$this调用对象中的其它方法.....................................................................................20
使用$this调用构造函数.................................................................................................21
$this 到底指的什么？...................................................................................................21
通过 $this 传递对象.....................................................................................................22
2.5 parent::关键字...............................................................................................................23
通过parent::调用父类方法.............................................................................................23
父类的private属性..........................................................................................................24
2.5 重载 Overload...............................................................................................................29
在PHP5中不支持重载。..............................................................................................29
2.7 实例.................................................................................................................................31