Why doesn't preventDefault() work?

Question

JavaScript

Why doesn't preventDefault() work?

function showPopupOrder(event) {

  event.preventDefault();
  $('body').append('<div class="overlay"></div>').fadeIn("slow");
  $('.popup-order').fadeIn("slow");

}

Uncaught TypeError: Cannot read property 'preventDefault' of undefined

Answer 1

You forgot to pass an event to a function.
onclick="showPopupOrder(event)"