WeChat QR code, Alipay QR code, UnionPay QR code, etc. Merchants need to open the credit card collection function of QR code. If the merchant is not open, users can't pay by credit card. If necessary, consult the merchant. When using credit card to pay, ensure the security of network environment and avoid the risk of information leakage and theft. At the same time, we should also pay attention to the rules and restrictions on the use of credit cards to avoid unnecessary trouble.