加载 ，设计和工厂模式

//加载类：
include("./Ren.class.php");  
include "./Ren.class.php";

require("./Ren.class.php");
require "./Ren.class.php";

require_once("./Ren.class.php");
require_once "./Ren.class.php";

//自动加载类的方法
//所有的类文件要放在同一个目录下
//所有类文件的命名规则一致

function __autoload($classname)
{
	require $classname.".class.php";
}


$r = new Ren();


//设计模式
//1.单例模式
//类的计划生育
//1.让该类在外界无法造对象
//2.让外界可以造一个对象，做一个静态方法返回对象
//3.在类里面通过静态变量控制返回对象只能是一个

class Dog
{
	static $dx;
	public $test;
	
	private function __construct()
	{
		
	}
	
	static function DuiXiang()
	{
		//return new Dog();
		
		if(empty(self::$dx))
		{
			self::$dx = new Dog();
		}
		
		return self::$dx;
	}
}

$a = Dog::DuiXiang();


$b = Dog::DuiXiang();
$b->test="hello";


var_dump($a);

//工厂模式
class YunSuan
{
	public $a;
	public $b;
	
	function Jia()
	{
		return $a+$b;
	}
	function Jian()
	{
		return $a-$b;
	}
}

abstract class YuanSuan
{
	public $a;
	public $b;
	
	function Suan()
	{
	}
}

class Jia extends YuanSuan
{
	function Suan()
	{
		return $this->a+$this->b;
	}
}

class Jian extends YuanSuan
{
	function Suan()
	{
		return $this->a-$this->b;
	}
}

class Cheng extends YuanSuan
{
	function Suan()
	{
		return $this->a*$this->b;
	}
}

$j = new Cheng();
$j->Suan();
 

class GongChang
{
	static function ShengChan($f)
	{
		switch($f)
		{
			case "+":
				return new Jia();
				break;
			case "-":
				return new Jian();
				break;
			case "*":
				return new Cheng();
				break;
		}
	}
}


$r = GongChang::ShengChan("*");
$r->a=10;
$r->b=5;
echo $r->Suan();


?>