<?php
class Cart
{
//产品价格
const PRICE_BUTTER = 1.00;
const PRICE_MILK = 3.00;
const PRICE_EGGS = 6.95;
protected $products =array();
public function add($product,$quantity)
{
$this->products[$product] = $quantity;
}
public function getQuantity($product)
{
return isset($this->products[$product]) ? $this->products[$product] :
FALSE;
}
public function getTotal($tax)
{
$total = 0.00;
$callback =
function ($quantity,$product)use ($tax, &$total)
{
// echo __CLASS__ ."::PRICE_" . strtoupper($product);die;
$pricePerItem = constant(__CLASS__ ."::PRICE_" . strtoupper($product));
// echo $pricePerItem.'<br>';
$total += ($pricePerItem *$quantity) * ($tax + 1.0);
};
array_walk($this->products,$callback);
return round($total, 2);
}
}
$my_cart =new Cart;
// 往购物车里添加条目
$my_cart->add('butter', 1);
$my_cart->add('milk', 3);
$my_cart->add('eggs', 6);
// 打出出总价格,其中有 5% 的销售税.
print $my_cart->getTotal(0.05) . " ";
// The result is 54.29
?>