1. A method for generating a prompt message for network connection conversion, adapted to a LAN including a plurality of APs, and the method operated in a root AP among the plurality of APs, the method comprising:receiving a connection conversion command from a user device, wherein the connection conversion command designates a target AP among the plurality of APs, and the root AP instructing the target AP to issue a lock signal to at least one AP within a subnet for maintaining a connection between the at least one AP and the target AP and disconnect an original connection between the target AP and an originally-connected AP;
obtaining at least one wireless signal strength between the target AP and at least one AP among the plurality of APs for determining at least one connectable AP for the target AP;
obtaining at least one connection rate from the target AP through the at least one connectable AP to the root AP; and
generating a prompt message for connection conversion according to the at least one connection rate;
when the target AP re-connects with any AP of the LAN, the target AP issues a unlock signal to the at least one AP of the subnet, so as to release a lock relationship between the target AP and the at least one AP of the subnet.