php 購物車類的實現代碼(單例模式)

/** * php 購物車類 * 單例模式 * Edit bbs.it-home.org */ class Cart{ static protected $ins; //執行個體變數 protected $item = array(); //放商品容器 //禁止外部調用 final protected function __construct(){ } //禁止複製 final protected function __clone(){ } //類內部執行個體化 static protected function Getins(){ if(!(self::$ins instanceof self)){ self::$ins = new self(); } return self::$ins; } //為了能使商品跨頁面儲存，把對象放入session裡 public function Getcat(){ if(!($_SESSION['cat']) || !($_SESSION['cat'] instanceof self)){ $_SESSION['cat'] = self::Getins(); } return $_SESSION['cat']; } //入列時的檢驗，是否在$item裡存在. public function Initem($goods_id){ if($this->Gettype() == 0){ return false; } if(!(array_key_exists($goods_id,$this->item))){ return false; }else{ return $this->item[$goods_id]['num']; //返回此商品個數 } } //添加一個商品 public function Additem($goods_id,$name,$num,$price){ if($this->Initem($goods_id) != false){ $this->item[$goods_id]['num'] += $num; return; } $this->item[$goods_id] = array(); //一個商品為一個數組 $this->item[$goods_id]['num'] = $num; //這一個商品的購買數量 $this->item[$goods_id]['name'] = $name; //商品名字 $this->item[$goods_id]['price'] = $price; //商品單價 } //減少一個商品 public function Reduceitem($goods_id,$num){ if($this->Initem($goods_id) == false){ return; } if($num > $this->Getunm($goods_id)){ unset($this->item[$goods_id]); }else{ $this->item[$goods_id]['num'] -=$num; } } //去掉一個商品 public function Delitem($goods_id){ if($this->Initem($goods_id)){ unset($this->item[$goods_id]); } } //返回購買商品列表 public function Itemlist(){ return $this->item; } //一共有多少種商品 public function Gettype(){ return count($this->item); } //獲得一種商品的總個數 public function Getunm($goods_id){ return $this->item[$goods_id]['num']; } // 查詢購物車中有多少個商品 public function Getnumber(){ $num = 0; if($this->Gettype() == 0){ return 0; } foreach($this->item as $k=>$v){ $num += $v['num']; } return $num; } //計算總價格 public function Getprice(){ $price = 0; if($this->Gettype() == 0){ return 0; } foreach($this->item as $k=>$v){ $price += $v['num']*$v['num']; } return $price; } //清空購物車 public function Emptyitem(){ $this->item = array(); } } ?> 複製代碼 調用樣本： include_once('Cart.php'); $cart = Cart::Getcat(); $cart->Additem('1','php學習教程(程式員之家版)','5','9999'); print_r($cart); ?> 複製代碼

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