How is she going to learn to stop attacking your feet if she is locked in a cage all night? 
Cats need to run and play.
Play with her for an hour or so before you go to bed, wear her out. Then she will not want to play with your feet under the sheets. Keep a spray bottle next to the bed. When she goes for the feet, squirt her. (avoiding face) She will learn that that is not such a fun game after all.
Caging her up will teach her nothing. What it will do is make her so crazy to run she will be getting into mischief all day.
Cats need to run and play.
Play with her for an hour or so before you go to bed, wear her out. Then she will not want to play with your feet under the sheets. Keep a spray bottle next to the bed. When she goes for the feet, squirt her. (avoiding face) She will learn that that is not such a fun game after all.
Caging her up will teach her nothing. What it will do is make her so crazy to run she will be getting into mischief all day.