How to Check whether a user clicked 'Ok' or 'Cancel' while using Confirm() function?

if (confirm('Are You Sure?')){
   window.location = "http://www.google.com/";
}else{
   alert("You are not redirected.")
}

DOCUMENTATION

You need to get the return value of confirm, and then decide what to do next.

var answer = confirm('Are You Sure');
if (answer) {
   //...
} else {
   //...
}