php設計模式——簡單工廠模式

工廠模式，工廠類就是用來生成特定的對象類，然後用特定的對象類來處理特殊的業務需求。

<?php
/**
 * 操作類
 */
abstract class operation{
	public $numA = 0;
	public $numB = 0;

	public function setVal($a, $b){
		$this->numA = $a;
		$this->numB = $b;	
	}
	
	abstract public function getResult();
}

/**
 * 具體實現類
 */
class operationAdd extends operation{

	public function getResult(){
		return $this->numA + $this->numB;
	}
}

class operationSub extends operation{

	public function getResult(){
		return $this->numA - $this->numB;
	}
}

/**
 * 簡單工廠類
 */
class operationFactory{
	
	public static function createOperation($operate){
		switch($operate){
			case 'add':
				$operationObj = new operationAdd();
				break;
			case 'sub':
				$operationObj = new operationSub();
				break;
		}
		return $operationObj;
	}
}

$a = 10;
$b = 5;
$operation = operationFactory::createOperation('add');
$operation->setVal($a, $b);
$result = $operation->getResult();
echo $result;