Php shopping cart class implementation code (Singleton mode)

Php shopping cart class implementation code (Singleton mode)

/** * Php shopping cart * Singleton mode * Edit bbs.it-home.org */ Class Cart { Static protected $ ins; // instance variable Protected $ item = array (); // puts the commodity container // Disable external calls Final protected function _ construct (){ } // Clone prohibited Final protected function _ clone (){ } // Class internal instantiation Static protected function Getins (){ If (! (Self: $ ins instanceof self )){ Self: $ ins = new self (); } Return self: $ ins; } // To save the product 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']; } // Check whether the column is included in $ item. 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']; // return 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 (); // an item is an array $ This-> item [$ goods_id] ['num'] = $ num; // quantity of items purchased $ This-> item [$ goods_id] ['name'] = $ name; // item name $ This-> item [$ goods_id] ['price'] = $ price; // unit price } // Reduce a commodity Public function performanceitem ($ 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 commodity Public function Delitem ($ goods_id ){ If ($ this-> Initem ($ goods_id )){ Unset ($ this-> item [$ goods_id]); } } // Return to the list of purchased items Public function Itemlist (){ Return $ this-> item; } // Total number of items Public function Gettype (){ Return count ($ this-> item ); } // Obtain the total number of items Public function Getunm ($ goods_id ){ Return $ this-> item [$ goods_id] ['num']; } // Query the number of items in the 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 the 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; } // Clear the shopping cart Public function Emptyitem (){ $ This-> item = array (); } } ?> Call example: Include_once ('cart. php '); $ Cart = Cart: Getcat (); $ Cart-> Additem ('1', 'php tutorial (Programmer's house Edition) ', '5', '123 '); Print_r ($ cart ); ?>