will my hair straightener work in Switzerland and France?
It will if it is "dual voltage".
Kathleen, To answer that question, you'll have to look at the specifications printed on the Straightener. Look for the words "Input Voltage". If this states "100-240 VAC, 50/60 Hz", then it will work in Europe. Of course, appropriate Plug Adapters will be required. You may wish to have a look at the Magellans website as they have a good selection of dual-voltage hair appliances. Happy travels!