How to save the state of a iPhone Switch and print it out?

How to save the state of a iPhone Switch and print it out?

I have a switch on my ViewController, and whenever I press the save
button, I want to use NSLog to print out if the switch is On/Off.
My question is, What data type saves the state of a switch? And how would
I print out that variable with the state?
EDIT:
If it was a DatePicker, it would be
@property (nonatomic, strong) NSDate *pickerDate;
I need the Switch version of this. NSSwitch doesn't seem to work.