PHP Shopping Cart class implementation code (Singleton mode)

/** * PHP Shopping Cart Category * Single case mode * Edit bbs.it-home.org */ Class cart{ static protected $ins; Instance variable protected $item = Array (); Put commodity containers Prohibit external calls Final protected function __construct () { } Prohibit cloning Final protected function __clone () { } Inner instantiation of class Static protected function Getins () { if (! ( Self:: $ins instanceof Self)) { Self:: $ins = new self (); } Return self:: $ins; } In order to enable the product to be saved across pages, put the object into the session Public Function Getcat () { if (! ( $_session[' cat '] | | ! ($_session[' cat '] instanceof self)) { $_session[' cat '] = Self::getins (); } Return $_session[' cat ']; } into row when the test, whether in the $item exist. Public Function Initem ($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 ']; Returns the number of items } } Add a Product 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 (); A product is an array $this->item[$goods _id][' num '] = $num; The number of purchases for this item $this->item[$goods _id][' name '] = $name; Product Name $this->item[$goods _id][' price ' = $price; Commodity price } Reduce one item Public Function Reduceitem ($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 ']-= $num; } } Remove a product Public Function Delitem ($goods _id) { if ($this->initem ($goods _id)) { unset ($this->item[$goods _id]); } } Back to list of purchased items Public Function Itemlist () { return $this->item; } How many kinds of goods are there? Public Function Gettype () { Return count ($this->item); } Get the total number of a product Public Function getunm ($goods _id) { return $this->item[$goods _id][' num ']; } Find out how many items are in your shopping cart Public Function GetNumber () { $num = 0; if ($this->gettype () = = 0) { return 0; } foreach ($this->item as $k = + $v) { $num + = $v [' num ']; } return $num; } Calculate Total Price Public Function GetPrice () { $price = 0; if ($this->gettype () = = 0) { return 0; } foreach ($this->item as $k = + $v) { $price + = $v [' num ']* $v [' num ']; } return $price; } Empty shopping Cart Public Function Emptyitem () { $this->item = Array (); } } ?> Copy Code Invocation Example: Include_once (' cart.php '); $cart = Cart::getcat (); $cart->additem (' 1 ', ' PHP Learning Tutorial (Programmer's Home version) ', ' 5 ', ' 9999 '); Print_r ($cart); ?> Copy Code

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