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JavaScript JavaScript and the DOM (Retiring) Making Changes to the DOM Styling Elements

Posted by Jaime Aguilar
Jaime Aguilar
7,651 Points

how can I declare the function later in the script rather than putting it in the event listener?

at 3:51 in the video

tobiastrinkler
.a{fill-rule:evenodd;}techdegree
tobiastrinkler
Full Stack JavaScript Techdegree Student 16,538 Points

Hi Jaime, you would have to pass the function as a argument to the eventlistener. You can name your function any name you want. I chose the name myFunction for this example. Hope this answers your question.

toggelList.addEventListener('click', myFunction);


function myFunction(){
//code goes here//
}

1 Answer

Jaime Aguilar
Jaime Aguilar
7,651 Points
Jaime Aguilar
Jaime Aguilar
7,651 Points

would it still work if the function that you're passing is an arrow function also? i can get my code to work if its an arrow function but i can if its a standard function.

tobiastrinkler
.a{fill-rule:evenodd;}techdegree
tobiastrinkler
Full Stack JavaScript Techdegree Student 16,538 Points

The problem is that when you declare an arrow function it has to be declared before the event listener is created. When using a function declarationit does not matter where the function is created in the document.

Arrow function:

let ul = document.querySelector('ul');

const myFunction = (e)=>{
   e.target.style.color = 'red';
  }

ul.addEventListener('click', myFunction);

Function declaration:

let ul = document.querySelector('ul');



ul.addEventListener('click', myFunction)

function myFunction(e){
  e.target.style.color = 'red'

}