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JavaScript

Posted by Alina Antemir
Alina Antemir
10,185 Points

what does e from (e) => stands for?

Hi,

I don't understand how the function (e) => works. What is 'e' ?

Can you please explain?

Thank you, Alina

3 Answers

Jesus Mendoza
Jesus Mendoza
23,289 Points
Jesus Mendoza
Jesus Mendoza
23,289 Points

Hey Alina,

Whenever you add an event listener to an element you need to pass an event handler (callback) right?

element.addEventListener('click', (e) => {
    console.log(e);
});

When the event is fired, that callback function is called and recieves one argument (e), that parameter contains all all the information of the event that just happened. If you log (e) you will see all that information.

Have a nice day!

Alexander Davison
Alexander Davison
65,469 Points
Alexander Davison
Alexander Davison
65,469 Points

I recommend watching this workshop to get an idea of Arrow-function syntax. It is a pretty handy tool just to create a function with less code.

The basic idea is that this:

(e) => {
}

Is the same as this:

function (e) {
}

I hope this helps. ~Alex

Alina Antemir
Alina Antemir
10,185 Points
Alina Antemir
Alina Antemir
10,185 Points

Thank you guys for the answers. It's all clear now. :)