I think the first thing to really be cognizant of as far as eating and working out is that you do not want to be walking in the gym and eating. I see this happen way too often. I'm on the treadmill, I'm warming up and somebody will walk in the gym with a container of chicken and rice or whatever. Then I'll see this same guy 20 minutes later on the treadmill running or trying to work out.
You your blood flow needs to be working towards the very goal of why you're in the gym, working towards your heart and your muscles and taking care of working hard to handle the weight that you're going to be throwing at it with the resistance training. So you want to make sure that whatever you eat before you work out you give yourself at least an hour, an hour and a half, minimum, to digest that food.
And it should be something light. It should be something quick. Cottage cheese and maybe some berries. It could be yogurt maybe with a scoop of protein powder in it. It could even be yogurt or cottage cheese with some quick oats mixed in. I actually take quick oats, oatmeal, and throw them in my protein shakes and I drink that down literally sometimes before a work out. A handful of nuts sometimes and a high glycemic piece of fruit, along with a little bit of protein works well.
Make sure that you're giving yourself enough time. It could even be something more substantial too, like some lettuce and some tuna fish. You just want to make sure you have the time to digest it and you don't want to overdo the portion prior to a work out. If you remember those guidelines then you'll be fine once you get into the gym. You'll have plenty of energy but you won't feel weighed down, which is the last thing you want before a work out.