Mickey48,
Probably not. There are parasitic items in the trailer that consume very small amounts of electricity all the time. Radio or TV, Smoke and CO detector are two of them.
You will find that the battery will only last about two weeks before being discharged.
When leaving my trailer for extended periods without elec hookups, I used to just disconnect one of the battery cables from the battery. Easy to do and there is no question of whether the battery will be drawn down by "phantom" electrical items in the trailer.:)
Barney