来自NetworkManager - ArchWiki的一段介绍：

NetworkManager also prefers wired connections over wireless ones, has support for modem connections and certain types of VPN.                        #NetworkManager (简体中文) - ArchWiki内容有点老，遂取自英文Wiki。

Use dispatcher to automatically toggle wireless depending on LAN cable being plugged in

The idea is to only turn Wi-Fi on when the LAN cable is unplugged (for example when detaching from a laptop dock), and for Wi-Fi to be automatically disabled, once a LAN cable is plugged in again.

Create the following dispatcher script[6], replacing LAN_interface with yours.

/etc/NetworkManager/dispatcher.d/wlan_auto_toggle.sh

#!/bin/sh

if [ "$1" = "LAN_interface" ]; then
    case "$2" in
        up)
            nmcli radio wifi off
            ;;
        down)
            nmcli radio wifi on
            ;;
    esac
fi