Embodiments of the present application disclose a method and system for recording purchase data performed by a first terminal device and a second terminal device. During operation, the first terminal device receives a command to record purchase data. In response to receiving the command to record purchase data, the first terminal device scans a digital object identifier generated by the second terminal device. The digital object identifier includes purchase data acquired by the second terminal device. The first terminal device then extracts and records the purchase data from the digital object identifier.