My iPhone 4s will not charge.

This morning, I unplugged my phone to go to school and its battery was at 100%. I put away and did not take it out again until lunch time. I unlocked my phone, and then got a notification that my phone was at less than 10% of its battery, and then I looked and saw that it was at 1% right before it died. So when I got home, I tried charging it, but even when I got it to turn back on, it would stay at 1%. I charged it for about 45 minutes. When I tried unplugging it, it died immediately and now will not even turn back on. I've tried 3 different chargers already, and have rebooted it and turned it on and off multiple times. I don't know if my battery has broke or what, but does anyone know how to fix this?