how to reduced stock when an item is added to the cart

in this video i am going to show you that how to reduced stock when an item is added to the cart means if available quantity is 5 in product table and when you do add to cart 1 item then we have to update the stock and we have to do stock qual to 4. you can learn how to Decrease stock as soon as a product is added to cart,how to reduced stock when an item is added to the cart,Reduce stock directly after item added to cart,how to create shopping cart in asp net using c#,add to cart code in asp.net with cookies, shopping cart asp.net c#,asp.net shopping cart tutorial