Product review (5 stars): Repaired my dryer in less than 30 minutes!
If the light inside your dryer stops working, and opening the door during a cycle does not stop the dryer from running, it probably means the switch needs to be replaced. This part was about ten dollars vs parts and labor from a repair company, which would likely be close to a hundred dollars.

I was able to find the instructions to repair the dryer through a web search, I recommend viewing the instructions FIRST to make sure you are comfortable with the repair (or if you know a handy person who can do it for you). The repair is pretty basic (other than one very awkward screw for the switch, so having another person to help might make it easier), of course different models may vary. I only needed a flathead and philips screwdriver.

I did the repair almost 1 year ago and so far the switch is working great. If it wears out again I will definitely purchase another of these switches.