A detecting method for determining that a user carrying a portable device arrives in an area, comprising: searching, by a portable device at a preset frequency for a wireless access device having a wireless access function located in the area according to an instruction, wherein the preset frequency is changed based on a searching duration and said frequency refers to how often the search is performed; after the wireless access device is searched out, establishing, by the portable device a connection with the wireless access device; and after the connection with the wireless access device is established, determining, by the portable device that a user arrives at the area, wherein searching for the wireless access device located in the area at the preset frequency according to the instruction comprises: when detecting, by the portable device that the user is about to arrive at the area, searching for the wireless access device at the preset frequency, wherein detecting, by the portable device that the user is about to arrive at the area comprises: sending, by the portable device a broadcast message to a Bluetooth device located within a certain distance from the area via Bluetooth, such that the Bluetooth device returns a response message after receiving the broadcast message; after receiving the response message, determining that the user is about to arrive at the area; or acquiring, by the portable device via self-positioning the user's position; determining a distance between the user's position and a pre-stored position of the area; when the distance between the user's position and the pre-stored position of the area is smaller than a predetermined distance, determining that the user is about to arrive at the area. searching, by a portable device at a preset frequency for a wireless access device having a wireless access function located in the area according to an instruction, wherein the preset frequency is changed based on a searching duration and said frequency refers to how often the search is performed; after the wireless access device is searched out, establishing, by the portable device a connection with the wireless access device; and after the connection with the wireless access device is established, determining, by the portable device that a user arrives at the area, wherein searching for the wireless access device located in the area at the preset frequency according to the instruction comprises: when detecting, by the portable device that the user is about to arrive at the area, searching for the wireless access device at the preset frequency, wherein detecting, by the portable device that the user is about to arrive at the area comprises: sending, by the portable device a broadcast message to a Bluetooth device located within a certain distance from the area via Bluetooth, such that the Bluetooth device returns a response message after receiving the broadcast message; after receiving the response message, determining that the user is about to arrive at the area; or acquiring, by the portable device via self-positioning the user's position; determining a distance between the user's position and a pre-stored position of the area; when the distance between the user's position and the pre-stored position of the area is smaller than a predetermined distance, determining that the user is about to arrive at the area. when detecting, by the portable device that the user is about to arrive at the area, searching for the wireless access device at the preset frequency, wherein detecting, by the portable device that the user is about to arrive at the area comprises: sending, by the portable device a broadcast message to a Bluetooth device located within a certain distance from the area via Bluetooth, such that the Bluetooth device returns a response message after receiving the broadcast message; after receiving the response message, determining that the user is about to arrive at the area; or acquiring, by the portable device via self-positioning the user's position; determining a distance between the user's position and a pre-stored position of the area; when the distance between the user's position and the pre-stored position of the area is smaller than a predetermined distance, determining that the user is about to arrive at the area. sending, by the portable device a broadcast message to a Bluetooth device located within a certain distance from the area via Bluetooth, such that the Bluetooth device returns a response message after receiving the broadcast message; after receiving the response message, determining that the user is about to arrive at the area; or acquiring, by the portable device via self-positioning the user's position; determining a distance between the user's position and a pre-stored position of the area; when the distance between the user's position and the pre-stored position of the area is smaller than a predetermined distance, determining that the user is about to arrive at the area.