<?php
/**
 * 策略抽象類
 * @author wzy
 *
 */
interface Strategy
{
  public function calPrice ($price);
}
/**
 * 普通會員策略類
 *
 * @author wzy
 *
 */
class PrimaryStrategy implements Strategy
{
  public function calPrice ($price)
  {
    echo "普通會員無折扣";
    return $price;
  }
}
/**
 * 中級會員策略類
 *
 * @author wzy
 *
 */
class MiddleStrategy implements Strategy
{
  public function calPrice ($price)
  {
    echo "中級會員8折優(yōu)惠";
    return $price * 0.8;
  }
}
/**
 * 高級會員策略類
 *
 * @author wzy
 *
 */
class HighStrategy implements Strategy
{
  public function calPrice ($price)
  {
    echo "高級會員7折優(yōu)惠";
    return $price * 0.7;
  }
}
/**
 * Context實(shí)現(xiàn)類
 *
 * @author wzy
 *
 */
class Price
{
  /**
   * 具體的策略類對象
   *
   * @var object
   */
  private $strategyInstance;
  /**
   * 構(gòu)造函數(shù)，傳入一個(gè)具體的策略對象
   *
   * @param object $instance
   */
  public function __construct ($instance)
  {
    $this->strategyInstance = $instance;
  }
  /**
   * 計(jì)算貨品的價(jià)格
   *
   * @param double $price
   */
  public function quote ($price)
  {
    return $this->strategyInstance->calPrice($price);
  }
}
/**
 * 客戶端操作
 */
$high = new HighStrategy();
$priceClass = new Price($high);
$price = $priceClass->quote(400);
echo $price;
?>