But, most of such measures won't give you 100% results as most of them will work only when the requirements are there and when such gambling addicts get access to internet then his/her gambling urge will reawake and the addiction will be much more intense then the previous time.
I only working and effective treatment to gambling addiction or any other type of addiction is to make some proper disciplinary rules for the addicts and change their attention from gambling to something else each day. For some addicts physical relationship works as a remedy while for others sports may be a better cure. There is still no guarantee that those addicts will give up on the addiction forever.
This is a two-way help when it comes to stopping gambling addiction, I don't think turning off the internet will be a good solution since we can put that to good use.
IMO, a good solution will always be to find a new hobby, get busy at something else, work, family, friends, etc... In that way, you will forget about it. A day without gambling is a good start. In my case, I am not addicted but I do have fun watching television series which takes my eyes off gambling.
Finding that new hobby will be easy just by sorting the likes of one person. Someone must like something else other than gambling, right?