Fly Tape and the Gnat Problem

I've got a real big gnat problem, inside and out. I'm trying a couple of things. The first was a brand of insecticidal soap spray from Schultz, which is not working and the second is good, old-fashioned fly-tape, which I picked up at the 99 cent store. I got four rolls for 99 cents, a great bargain! I was told about using tape at the California Cactus Center, but I wasn't sure about it. Within about an half-an hour I had all those gnats stuck at the top. Needless to say, I was shocked. I have one hanging by my tomato plants, which have a really bad infestation. I have to say that though that my tomatoes aren't doing so good generally anyway. I have some little caterpillar eating up all my plants. Darn caterpillar! At least you can pick them off fairly easy though. Still they ate a bunch of leaves before I caught on to them. Anyway, back to the gnats: I'm hoping the tape will eliminate a few of them from laying more eggs! Imagine all those babies!