<?php
class A{
function __construct(){
$this->say();
$this->hello();
}
protected function say(){
echo __CLASS__."[A]<br/>";
}
private function hello(){
echo "[a]hello<br/>";
}
}
class B extends A{
function __construct(){
parent::__construct();
$this->say();
$this->hello();
}
function say(){
echo __CLASS__."[B]<br/>";
}
function hello(){
echo "[b]hello<br/>";
}
}
$a=new B();
?>
output:
B[B]
[a]hello
B[B]
[b]hello
parent::__construct()执行时 say方法是子类的,而hello类是父类的,差异十分明显