[lua]原来这才是表驱动的正确表达方式

function event_do( event )
    -- event:string
    local handler ={}
    function handler.touchBegin()
        print("handler.touchBegin")
    end
    function handler.touchEnd()
        print("handler.touchEnd")
    end

    local event_handler = handler[event]
    return event_handler and event_handler()
end

event_do("touchBegin")

event_do("touchEnd")