<?php
/*
1、继承那些东西 public protected子类属性方法 可操作
2、子类可以做什么扩充
3、构造函数如何继承
4、私有的属性和方法如何继承
*/
header('Content-Type:text/html;charset=utf-8');
class Human
{
private $wife = '小甜甜';
//如果去掉 Cannot access private property Stu::$wife
public function hshow()
{
echo $this->wife . "<br>";
}
}
class Stu extends Human
{
private $wife = '凤姐';
//如果去掉产生 Undefined property: Stu::$wife 错误
public function sshow()
{
//parent::hshow();//使用parent会更快一点
$this->hshow();
echo $this->wife . "<br/>";
}
}
$stu = new Stu();
$stu->sshow();
*
* self:本类
* parent:父类
*
* 在引入自身的静态方法/静态属性
* 以及父类的方法，属性时用到
*
*/
class Human
{
public static $head = 1;
public $age = 28;
public function say()
{
echo $this->age;
}
public function show()
{
echo self::$head, 'hello<br />';
}
}
class Stu extends Human
{
public function show()
{
parent::show();
echo 'world';
}
}
$m = new Stu();
$m->show();
}
class Stu extends Human{
}
class FreshMan extends Stu{
public function Say(){
echo '我要出国，做美得坚人!<br/>';
}
}
echo 'final修饰的方法可以继承<br />';
$ming = new Stu();
$ming->Say();
$ming->show();
echo '但不可以修改<br />';
$fr = new FreshMan();
$fr->Say();
$fr->show();
/*
Fatal error: Cannot override final method Human::Say()
*/
?>
echo $this->wife,'<br />';
}
public function cry(){
echo '5555<br />';
}
}
class Stu extends Human{
public function subtell(){
echo $this->wife;
}
}
$lisi = new Stu();
$lisi -> cry();
$lisi -> tell();
$lisi -> subtell(); //不能调用，因为子类不没有wife
/*
未定义的属性,wifi属性
私有属性，可以理解不能继承
（其实是能继承过来，只不过无法访问）
public protected private中，
public protected 都可以继承，并拥有访问和修改的权限
这就好比说，家产已经了，愿意卖就卖
*/
class Human{
public function say($name){
echo $name, '吃了吗？<br />';
}
}
class Stu extends Human{
public function say(){
echo 'Yo Yo 切克闹!<br />'; //上面这个过程叫重写override
}
}
$ming = new Stu();
$ming->say();
$ming->say('张三');
/*
可以灵活的模拟像Java中的函数重载的效果
*/
class Calc{
public function area(){
//判断一个调用area时，得到的参数个数
$args = func_get_args();
if(count($args) == 1){
return 3.14 * $args[0];
}else if(count($args) == 2){
<?php
/**
* private_protected_public
*
*
*/
class Human
{
private $name = 'zhangsan';
protected $money = 3000;
public $age = 28;
public function say()
{
echo $this->name, '<br />';
echo $this->money, '<br />';
echo $this->age, '<br />';
}
}
class Stu extends Human
{
private $friend = 'xiaozhu';
public function talk()
{
echo $this->name, '<br />';
echo $this->money, '<br />';
echo $this->age, '<br />';
}
}
$ming = new Stu();
$ming->talk();
private $wife = '小甜甜';
protected $age = 39;
public function tell()
{
echo $this->wife, '<br />';
}
public function cry()
{
echo '555555<br />';
}
public function hShow()
{
echo $this->wife, '<br />';
}
}
class Stu extends Human
{
private $wife = '小猪猪';
public function sShow()
{
parent::hShow();
echo $this->wife, '<br />';
}
public function getAge()
{
return $this->age = 20;
}
}
$lisi = new Stu();
echo '<pre>';
echo $lisi->getAge();
}
class Stu extends Human{
private $wife = '美女老师';
public $height = 170;
public function subtell(){
echo $this->wife,'<br />';
}
//子类自己的工作
public function SWork(){
parent::Work(); //继承父的工作
echo '<br /> 打铁'; //自己又会打铁
}
}
$lisi = new Stu();
$lisi -> subtell();
$lisi -> SWork();
echo '<pre>';
print_r($lisi);
echo '</pre>';
?>
后期绑定/延迟绑定
*/
header("Content-Type:text/html; charset=utf-8");
class Human{
public static function whoami(){
echo '来自父类的whoami在执行<br />';
}
public static function say(){
self::whoami(); //子类内没有say方法，找到父类这里 self是指父类
}
public static function say2(){
static::whoami(); //子类也没有say2方法，又找到父类这里
//但是父类用static::whoami
//指调用你子类自己的whoami方法
}
}
class Stu{
public static function whoami(){
echo '来自子类的whoami在执行<br />';
}
}
Stu::say();
Stu::say2();
?>
*
*
* 重载/ overloaded
*/
header('Content-type:text/html;charset=utf-8');
/**
* 重写例子
*/
class Human
{
public function say()
{
echo '吃了吗';
}
}
class Stu extends Human
{
public function say()
{
echo 'hello';
}
// public function say($a,$b,$c) {
// echo '哥三好';
// }
public function oldSay()
{
parent::say();
}
}
$s = new Stu();
$s->say();