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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

How to pass a reference to function?

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

select.addEventListener('change', ___);

I got the annswer is handleChange but why? Thanks

1 Answer

Peter Vann
Peter Vann
36,426 Points

Hi Hanwen!

That confused me at first, too.

A reference to a function is just its name (leaving off the (), because you are not running it yet).

Later it will be ran/executed by calling it (or "invoking it") by using handleChange();

(In this case, "later" is whenever select is changed.)

I hope that helps.

Stay safe and happy coding!

Hanwen Zhang
Hanwen Zhang
20,084 Points

Hi Peter,

Thank you for your explanation.