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JavaScript

Posted by Michael MacKenzie
Michael MacKenzie
8,633 Points

When I use an arrow function it works, but not when I use a function declaration.

All of my syntax is correct and I can get it working correctly but only when I use an arrow function. When I try to switch it to a normal function it starts applying the style as soon as I refresh the page before I even click. I have used normal functions to do similar things in my own little projects and they worked. Can anyone tell me why my normal function wont work here?

const p = document.getElementById('btn-main');

p.addEventListener('click', myFunc() );

function myFunc () {
 document.getElementById('headline').style.border = '1px solid red'; 
}

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

When you put parentheses after a function name, it calls the function (immediately). But in this case you only want to identify the function so the listener mechanism can call it later when the click event occurs.

p.addEventListener('click', myFunc() );    // so instead of this ....
p.addEventListener('click', myFunc );      // just do THIS

You did not show an example of the arrow function, but I'd guess you were coding it in-line, so it was just being defined and not immediately called.