Yeah. All the ballasts I've pulled from goods are usually labeled type one outdoor. The preheat chokes are called that too, and the electronic ones are usually tar potted or have a water tight seal in the case.

It is by far not only electronic, but all electrical stuff really has to be kept away. Of course, with the lamps alone that is not possible, but nothing else should not remain close to the water. Don§t forget the water is usually heated above the room temperature (at least with the fresh water aquariums, common here), that means the water mass will always be warmer than the things above, unless the things are heated as well.
As the light usus to be switched OFF for part of the day, it cools down. And at that point the water will always condense on it.
I've seen attempts to make "sealed boxes", but the real life had shown that does not work either, as the sealing is usually not pressured gas tight: As the thing warms up when operated, the air inside expands, so get pushed out by quite some pressure. Then when it cools down, the air contracts, creates partial vacuum and suck in the air from the outside. Include the moisture.
The result was, the chokes became rusty after few months of use, failing after just few years.

So the only way to prevent this is to really keep all these things away from the humid air - just behind or beside the tank it is usually perfectly OK. The water vapor is lighter than the air (about 2x), so it will only rise and there dilute with the other air, it will never go down. Of course, if it forms mist, these droplets are heavier, but forming a mist from just evaporated water would require really high temperature of the water mass, but that is never the case with aquariums.