Confirm before a form submit

Question

I have searched for an answer but couldn\'t find one!

I have a simple form,

Answer 1

var submit = document.querySelector("input[type=submit]");
  
/* set onclick on submit input */   
submit.setAttribute("onclick", "return test()");

//submit.addEventListener("click", test);

function test() {

  if (confirm('Are you sure you want to submit this form?')) {         
    return true;         
  } else {
    return false;
  }

}