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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Callback Functions Review

Posted by Hanwen Zhang
Hanwen Zhang
20,084 Points

Pass addEventListener() a reference to the handleChange function.

Why this one is incorrect T^T

1 Answer

Peter Vann
Peter Vann
36,425 Points

Hi Hanwen!

When they say "pass a reference to the function", that just means the name of the function.

For example: playSound would be how you type that function as a passed-in parameter (meaning you leave the parens off, because you're not calling/running it yet).

When you then run it in the body of the function it was passed into, however, you'd use playSound();

Therefore the answer is:

function handleChange() {
  console.log('I was changed!');
}

select.addEventListener('change', handleChange); // Passed in only so far, and will run/execute only when select changes

I hope that helps.

Stay safe and happy coding!

Hanwen Zhang
Hanwen Zhang
20,084 Points

Understood now, thank you