Shanghai Carrefour card can still be used because Carrefour still exists and operates in the market. Carrefour card is an effective shopping card and can be used in Carrefour supermarket. With the development of e-commerce, Carrefour has also opened an online shopping platform, and Carrefour cards can be used online. As long as Carrefour continues to operate, the Carrefour card can continue to be used.