Method and communications device for changing electronic cards without power off

In a method and communications device for changing electronic cards without power off, the communications device includes a control module, a card connector for receiving an electronic card, and a trigger module. The method includes: (a) when the communications device is in an on state, enabling the trigger module to generate a trigger signal to the control module upon being actuated; (b) after receipt of the trigger signal, if the control module detects that a state of electrical connection of the card connector to the electronic card switches from a disconnected state to a connected state, the control module determining a card insertion mode; and (c) supplying power to the electronic card connected to the card connector when the control module determines the card insertion mode.