<?php

//定义接口

interface Calc{

public function getValue($num1,$num2);

}

//创建实现接口的实体类

class Add implements Calc{

public function getValue($num1,$num2) {

return $num1 + $num2;

}

}

class Sub implements Calc{

public function getValue($num1,$num2) {

return $num1 - $num2;

}

}

class Mul implements Calc{

public function getValue($num1,$num2) {

return $num1 * $num2;

}

}

class Div implements Calc{

public function getValue($num1,$num2) {

try {

if($num2 == 0) {

throw new Exception('除数不能为0');

} else {

return $num1/$num2;

}

} catch (Exception $e) {

echo "错误信息：" . $e->getMessage();

}

}

}

//创建一个工厂，生成基于给定信息的实体类的对象

class Factory{

public static function createObj($operate) {

switch ($operate) {

case '+':

return new Add();

break;

case '-':

return new Sub();

break;

case '*':

return new Mul();

break;

case '/':

return new Div();

break;

}

}

}

$test = Factory::createObj('-');

echo $test->getValue(1,4);

?>

本文转自  陈小龙哈   51CTO博客，原文链接:http://blog.51cto.com/chenxiaolong/1790707