1     public function buy($goods_id = 0){  
 2         if(!$goods_id){  
 3             die("商品不存在！");  
 4         }  
 5         $redis = new Redis();  
 6         $redis->connect(‘127.0.0.1‘,6379);  
 7         $stock = 0;  
 8         if(!$redis->get("gid".$goods_id)){  
 9             $stock = get_stock($goods_id); //从数据看获取实际库存  
10             $redis->set("gid".$goods_id,$stock);  
11         }else{  
12             $stock = $redis->get("gid".$goods_id);  
13         }  
14       
15         if($stock > 0){  
16             //逻辑操作 代码  
17             //coding here...  
18             set("gid".$goods_id,$stock-1);  
19         }else{  
20             die("已卖完！");  
21         }  
22     }