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JavaScript jQuery Basics (2014) Creating a Simple Lightbox Perform: Part 1

Patrick Vanegas
Patrick Vanegas
6,971 Points
Posted by Patrick Vanegas
Patrick Vanegas
6,971 Points

Why do we never pass an "event" to the function?

I am confused as to why this works even though Andrew never passed an "event" to the anonymous function.

1 Answer

Lars Reimann
Lars Reimann
11,816 Points
Lars Reimann
Lars Reimann
11,816 Points

this is always set regardless of whether we specify the event as a parameter. Behind the scenes jQuery is calling the handler as if it was a method of the element. You must not use arrow functions for this to work though:

$('#imageGallery a').click((event) => {
  console.log($(this).attr('href'));
  event.preventDefault();
});

This will just print undefined, because this always points to the window object in this case and it does not have an href attribute. Note that I just pass in the event to prevent the default behavior of the browser, i. e. navigating to a new page.