An electronic device is provided, including a housing, at least one tap sensing unit and a processing unit. The housing has a touch surface, in which, when the touch surface is tapped more than one time in a predetermined interval, shock waves are generated. The tap sensing unit receives the shock waves to generate a moire signal. The processing unit obtains a shock wave source number of each of the shock waves according to the moire signal, and generates a string code according to a generation order of the shock waves and the shock wave source number of each of the shock waves, such that the processing unit controls the electronic device according to a control command corresponding to the string code.