An electronic system includes a first wireless transceiving module having a device identification code and a portable device. The portable device may include a second wireless transceiving module, a storage module, and a processor. The second wireless transceiving module obtains the device identification code from the first wireless transceiving module. The storage module may store at least one set of data, wherein each set of data may comprise a pre-built identification code and a corresponding pre-assigned instruction. When the second wireless transceiving module obtains the device identification code from the first wireless transceiving module, the processor may be able to search for the at least one set of data to check whether the device identification code matches to the pre-built identification code stored in the storage module; and when the device identification code matches to the pre-built identification code, the processor may automatically execute the corresponding pre-assigned instruction.